Mithrene Is a Self-Assembling Robustly Blue Luminescent Metal

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Mithrene is a Self-Assembling Robustly Blue-Luminescent MetalOrganic Chalcogenolate Assembly for 2D Optoelectronic Applications Elyse A. Schriber, Derek C. Popple, Matthew Yeung, Michael A. Brady, Stephen Corlett, and J. Nathan Hohman ACS Appl. Nano Mater., Just Accepted Manuscript • DOI: 10.1021/acsanm.8b00662 • Publication Date (Web): 20 Jun 2018 Downloaded from http://pubs.acs.org on June 22, 2018

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ACS Applied Nano Materials

Mithrene is a Self-Assembling Robustly Blue-Luminescent Metal-Organic Chalcogenolate Assembly for 2D Optoelectronic Applications Elyse A. Schriber,1 Derek C. Popple,1, 4 Matthew Yeung,1, 2 Michael A. Brady,1,3 Stephen Corlett,5 J. Nathan Hohman1* 1

Molecular Foundry, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California, 94720, United States 2 Ming Heish Department of Electrical Engineering, University of Southern California, Los Angeles, California, 90089, United States 3 Advanced Light Source, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California, 94720, United States 4 Department of Chemistry, University of California, Berkeley, Berkeley, California, 94720, United States 5 Departments of Astronomy, Physics and Chemistry, Laney College, Oakland, California 94607, United States Keywords: silver chalcogenide, metal-organic chalcogenolate; MOCHA; mithrene; MOC; 2D material; self-assembly; hybrid material

ABSTRACT: Crystalline metal-organic chalcogenolate assemblies are a class of semiconducting hybrid nanomaterials that consist of well-defined arrays of nanostructured inorganic coordination polymers with a supramolecular lattice of organic ligands. Growing crystals of periodic arrays of nanostructured hybrid chalcogenolates at biphasic liquid-liquid interfaces has been used to prepare semiconducting hybrid materials for potential applications in sensing, catalysis, mechanochemistry, organic light-emitting devices, and photovoltaics. However, a distinct lack of a systematic framework for quantifying the relationship between experimental parameters and the structure-function relationship of the prepared materials has been one of the largest hurdles for the emerging field of hybrid chalcogenolates and related hybrid coordination polymer systems. Here we examine the crystallization of silver benzeneselenolate, coined here as mithrene, at a toluene-water interface and demonstrate that silver ion concentration is the critical variable for controlling the morphology of the semiconducting crystals. Confocal microscopy is used to demonstrate that the blue luminescence of the material is robust across all morphologies. The role of metal ion concentration on the structure and morphology of the hybrid chalcogenolate is considered, and the properties of the crystalline and amorphous products are compared. Grazing incidence wide-angle X-ray scattering is used to demonstrate that the crystallographic phase of the crystals in sparse layers is uniform across all morphologies. The observation of blue luminescence can be used as a reliable proxy for the crystalline phase in future work. The straightforward synthetic preparation for and robust optoelectronic properties of silver benzeneselenolate make it an ideal model system for the development of device and sensor applications leveraging the emerging class of metal-organic chalcogenolates.

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Introduction Ultrathin two-dimensional (2D) nanomaterials like graphene or MoS2 monolayers have attracted interest for their strength and optoelectronic properties, and have been considered for applications in photovoltaics, light-emitting diodes, catalysis, and sensing.1-14 One key challenge of integrating ultrathin materials into devices is their intrinsic fragility. Hybrid organic-inorganic coordination polymers have been prepared that share structural and electronic properties with ultrathin materials like MoS2, but are found in a 3-dimensional (3D) bulk crystalline array.15-26 This 3D form factor makes them useful for applications where the 2D-like optoelectronic properties are desirable, but ultrathin structure is not an essential feature.27-31 Hybrid coordination polymers and metal-halide perovskites can have compelling nanoscale properties and can be prepared as stable crystals in high yield, where each crystal contains a periodic array of 1-dimensional (1D) or 2D nanostructures.30, 32-38 These inorganic nanostructures in such crystalline coordination polymers and clusters are isolated from one another, physically and electronically, by the supramolecular lattice composed of the organic ligands.18, 39-43 This approach affords the preparation of precise arrays of inorganic nanomaterials with a chemically configurable molecular sidegroup. The metal-organic chalcogenolate assemblies (MOCHAs) are an emerging class of crystalline materials that has garnered recent interest for semiconductor applications.26, 44-47 Recently, several examples of MOCHAs have been evolved at biphasic liquidliquid interfaces by the precipitation of an organic thiol against a solution of an aqueous salt.25-26 Although experimentally straightforward, biphasic interfacial synthesis is a complex three-phase chemical reaction environment consisting of two immiscible solutions and solid reaction products, and subtle changes in experimental variables can have a large impact on the structure, morphology, and purity of the precipitating materials.48-51 Additionally, since the yield of such interfacial reactions are low (0.1-1 mg), thorough assessment of the crystal structure and phase over a large parameter space can be challenging. Corrigan and coworkers first synthesized and reported a single crystal structure for silver benzeneselenolate, a layered nanostructured crystalline system comprised ultrathin inorganic 2D selenolate nanosheets and organic sidegroups. The crystal structure is shown schematically in Figure 1. They observed a UV-Vis absorption at around 434 nm,18 making the material a candidate for optoelectronic properties in the visible range, but no systematic study into the potential application of this compound as a semiconducting nanomaterial has been performed.47 Here, we report a single-step preparation for crystalline silver benzeneselenolate, [AgSePh]∞ and characterization of its robust emission properties. We found that this material exhibits robust blue luminescence at 467 nm. The blue emission is not impacted by crystal size, shape, or morphology. Two distinct products were observed: the crystalline, luminescent MOCHA, and a fibrous, amorphous, and non-luminescent metal-organic chalcogenolate polymer (MOCP). The crystalline phase was definitively linked to the emission properties, using a combination of synchrotronsource grazing incidence wide-angle X-ray scattering and confocal microscopy. A study of reagent concentration on crystal morphology in the few-mM range was performed and established that silver ion concentration is the major factor controlling the morphology of the crystalline phase and the abundance of the MOCP product. The straightforward synthesis, availability of welldefined step edges, organic perfunctionalization, and insensitivity of experimental parameters to semiconducting properties present opportunities for this and related materials to serve as the basis for hybrid light-emitting diodes, optical biosensors,52 in hybrid semiconductor devices,53 or for photocatalytic applications.

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Inspired by the intense blue luminescence and periodic array of ultrathin 2D hybrid nanosheets, we coined the name ‘mithrene,’ selecting the prefix ‘mith-’ as an homage to J. R. R. Tolkein’s fictional silvered steel ‘mithril,’ and added the suffix ‘-ene’ for the 2D inorganic layers isolated by a supramolecular framework.

Figure 1. a, b. Structural overview of the silver benzeneselenolate18 (mithrene) layered structure. The (001) face is the basal plane of the crystalline system. The colors silver = Ag, orange = Se, and the blue hexagons represent phenyl rings (C6H5). The layers are held together by van der Waals forces. RESULTS AND DISCUSSION Synthesis and Optoelectronic Uniformity of Mithrene Mithrene crystals were prepared using a single-step biphasic immiscible interface method similar to approaches reported previously, using reagent concentrations in the 1-10 mM range produce crystals of diamondoid-based d10 hybrid chalcogenolates.25-26 Figure 2 depicts the synthesis and products of the biphasic reaction using empirically selected concentrations of 3 mM silver nitrate in water and 3 mM diphenyl diselenide (DPSe) in toluene. A photograph of a typical reaction is shown in Fig. 2a. The insoluble precipitate at the liquid-liquid interface of the vial was transferred to a silicon wafer (Fig. 2b). The lamellar crystal [AgSePh]∞ exhibits a platy crystal habit when prepared at these conditions, and is shown in Fig. 2c. Scanning electron microscopy (SEM) resolved a smooth, featureless basal surface, attributed to the {001} crystallographic plane. Crystallographic step edges are observed in the high-resolution SEM images (Fig. 2e), and are attributed to the 1.4 nm inter-lamellar spacing. A 1:1 silver selenium ratio was confirmed by energy dispersive X-ray spectroscopy (EDS). Excitation by a 405 nm laser in a confocal microscope was used to examine the emissive properties of the crystals. Figs. 2f and 2g show optical and confocal micrographs, respectively, of mithrene crystals, and their uniform blue luminescence. The crystal structure was confirmed by matching X-ray diffraction (XRD) spectra to a literature reference for silver benzeneselenolate.18 Theoretical XRD patterns can be found in the supporting information Figures S1 and S2. For the moment, we will focus on the microscopy results, vide infra for the discussion of X-ray scattering results. We also observed a threadlike, amorphous, non-luminescent MOCP product that coevolves with the crystallites. The two products together form an insoluble film at the liquid-liquid interface that is easily transferred to a silicon wafer. High-resolution images of crystals with varying abundance of the MOCP are collected in Figure S3. EDS revealed a 2:1 silver-selenium ratio (Figure S4), distinctly different from the 1:1 ratio observed in the crystalline phase. Similar amorphous coordination polymer products have been observed in gold thiolates.54 Because light exposure to silver nitrate solutions is known to induce silver nanocrystal formation, we investigated whether illumination played a role on the formation of the MOCP and crystals, but samples held in the dark were indistinguishable from those exposed to indoor laboratory light.


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Figure 3. a. Absorption and emission spectra of mithrene crystal suspensions in isopropanol. At least two absorption features are evident at ~440 nm. All samples exhibit a uniform emission regardless of crystal growth duration. b. Color invariance recorded for 157 individual, isolated crystallites selected from a sample dropcast on a glass coverslip on a confocal microscope. Error bars denote differences in relative intensity. c. Distribution of emission intensity for the selected crystallites plotted as a function of crystal area and d. aspect ratio. The Pearson’s r-value for each set of data was calculated by using linear least squares fitting (dashed line); for both the plots the Pearson’s r-values indicate no correlation with intensity.

Role of Metal Ion Concentration on Crystal Morphology Figure 2. a. The two-component polymer layer precipitates at the toluene-water liquid interface. The yellow color of the toluene solution is from diphenyl diselenide. b. Harvesting method as described produces a sparse layer of crystals that are easily transferred to a silicon substrate. c. An optical micrograph of the precipitate film on a silicon substrate. d. Mithrene crystallites have edge lengths of 1-4 microns and a thickness of ~100 nm. e. Two mithrene crystals have intergrown. The step edges of the layered crystal are evident in the image. f. Optical and g. confocal micrographs of silver benzeneselenolate (mithrene) showing uniform luminescence of the crystalline phase.

To determine if the crystal size or shape affects the emission wavelength or intensity, single-crystals were examined by confocal microscopy using a 405 nm laser excitation. Suspensions of crystals in isopropyl alcohol were prepared for UV-visible absorption and photoluminescence emission measurements (Fig. 3a). The absorption feature at 434 nm reported by Corrigan and coworkers was observed. The high relative background is attributed to scattering by crystals in the suspension. Emission spectra were obtained from samples grown for 3, 5, and 10 days, and then normalized. No impact of crystal growth time on luminescent properties was observed. Measuring the shape and emission spectra of isolated non-overlapping crystals, we find that each crystal has an emission peak at 467 nm. No correlations between emission intensity and crystal aspect ratio or surface area were observed, as shown in Figure 3d and 3e. The analysis at the singleparticle level suggests that the photoluminescence intensity is not dependent on the lateral size dimensions of the crystal at the microscale. Instead, emission intensity correlates with crystal thickness, which relates to number of layers. Although absolute crystal thickness is not directly measured in this experiment, relative thicknesses may be inferred by visual inspection using the optical microscope.

Systematic control of crystal morphology is of critical importance55-58 because applications such as molecule adsorption, energy storage and catalysis are highly sensitive to local surface and atomic structures.59 Crystalline inorganic and hybrid materials have well-defined interfaces where fine details of structure and morphology can impact their performance. For example, recent studies have demonstrated structural and morphological control of similar classes of materials like metal-organic frameworks and zeolitic imidazolate frameworks.60-65 In another example, modulation of silver ion concentration has been previously linked to silver nanostructure morphology, as previously reported by Zhang, Sun, et.al.66 The development of a particular morphology depends on the relative rate of growth along different crystallographic directions.67 Experimental factors including concentration, temperature, solvent, and addition of surfactants can all be independently manipulated to direct crystal shape, and systematic approaches are required to investigate the role different variables play in the evolution from seed crystal to steady state morphology. Disentangling these myriad independent variables can be challenging, and controlling crystal growth can take on an artisanal aspect. In an example from nature, the morphologies observed in snowflakes are intimately sensitive to the precise combinations of environmental conditions68-69 and availability of specific nucleators such as bacteria, fungi, and other particles in the air.70-71 Ice crystal morphologies can be controlled in a laboratory setting by altering the cooling rate of the liquid from which they form.72 Crystal growth experiments were designed to test the role of reagent concentration. Earlier experiments had noted that varying reagent concentration could impact crystal habit, morphology and that the products were sensitive to the concentration used and the time employed.25-26 The link between reagent concentration and



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crystal morphology was tested by varying solution concentration of the two species in the few millimolar range. The results are collected in Figure 4, with companion schematic depiction of the characteristic crystal morphologies. The makeup and morphology of the product correlates to the concentration of silver nitrate, and a series of images of the various morphologies are collected in Figure 4c. At low concentrations of silver nitrate, the platy crystal habits are favored. Crystals formed at 5 mM to 10 mM silver nitrate showed branching growth projecting from the {100} and {010} planes, lending the crystals to adopt a wing-like or lenticular appearance. The “wing–like” morphology is attributed to twinning and stacking mismatches on the {001} plane. Variation of diphenyl diselenide concentration weakly correlates to the thickness of the crystals (supplementary information Figure S5). All crystals, regardless of dominant habit, are lamellar.

Figure 5. a. Optical density of harvested films is non-uniform across samples harvested from the same reaction. b. A higher density of mithrene protruding from the MOCP matrix is observed in the darker region of the film. c. The lighter colored region is largely smooth, with few protruding mithrene crystals. d. Numerous crystals protrude from the polymer matrix.

Figure 4. a. Crystallization of mithrene was performed at an immiscible liquid-liquid interface between an aqueous solution of silver nitrate and a solution of DPSe in toluene. b. Schematic of nucleating crystals that form pinned at the interface. c. SEM images of samples organized with silver concentration on the y-axis and growth time on the x-axis. Crystallite thickness is noticeable at lower concentrations of silver and branching of the crystals can be seen in the higher concentrations of silver. d. Schematic depiction of observed crystal habits complementary for each noted reaction condition. e. Surfactant-modification induces partial vertical growth inhibition of the {001} basal plane.

Figure 5 depicts a characteristic example of the mixture of products formed at higher concentrations of silver nitrate. Amorphous MOCP yield correlates with silver concentration, with MOCP dominating at higher silver concentration and longer growth times. Both of the products, the mithrene crystals and the amorphous MOCP, are observed. First, the abundance of MOCP is considerably higher relative to the number of crystals, which are sparse. Also, there are considerable local differences on crystal yield and MOCP thickness in the same sample. This is detailed in Figure 5a, where the optical density, the observed colors of the films, and crystal density all vary both across a single reaction and between them. For example, the orange-colored region on the lower left of Figure 5a has few crystals and appears smooth, and the material is predominantly comprised of the MOCP. On the right, the deposit is thicker, and the distorted crystallites protrude from the MOCP film, breaking the otherwise smooth polymer. High-resolution SEM imaging of both areas reveals differences in the nucleation density of the crystalline phase in closely separated regions of the same sample. Figures 5c and 5d depict perspective views of the films.

Addition of cationic surfactants, like cetytrimeythylammonium bromide (CTAB), can affect nucleation and growth of crystals by acting as a capping agent with preferential absorption to specific facets.73-75 We tested whether the same mechanism might serve to similarly to modify the growing mithrene crystals. Addition of CTAB to a concentration of 5 µM in an aqueous 3 mM silver nitrate solution was performed, but otherwise the reaction was identical to those previously discussed. In this range, addition of surfactant to the aqueous layer does not appear to affect nucleation and initial growth of the crystals, and all crystals were found to have overall dimensions in a similar range as those prepared without surfactants. However, extension in the vertical direction was strongly impacted. Figure 6 collects images of crystals revealing a distinctive Janus morphology, wherein one side of crystals were smooth, while the other had its basal {001} plane decorated with crystallographically aligned pillars of mithrene. The asymmetry is attributed to the partitioning of the surfactant across the liquid-liquid interface. Because CTAB is insoluble in toluene, and was only added to the aqueous layer, we hypothesize that the CTAB therefore preferentially modified the water-facing side of the crystal as it evolved. The role of CTAB on the surface tension of a toluene-water interface and mass transport across it has been examined previously.76 Whether the surfactant behaved as a true capping agent by preferential adsorption to {100} or {010} step edges during the thickening of the crystallites; impacted crystal adhesion and contact to the aqueous interface thereby modifying the microstructure as the crystal thickened; or modified mass transport across the CTAB-modified liquid-liquid interface remains a topic for further experiments and study.


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Figure 7. High-resolution SEM images of square shaped mithrene crystals with resolved lamellar stacking (top row) and all modified crystal habits with their corresponding confocal micrographs (bottom row). All crystals have the same emission characteristics. a. platy, or square-shaped mithrene crystals, b. “wing” morphologies, c. “rosette” morphologies and d. CTAB-modified crystals with attached crystallites yield “speckling” in the confocal micrograph, attributed to thickness variation across the otherwise uniform crystallites.

Figure 6: a. “Janus” mithrene crystallites grown in the presence of CTAB. One side of the crystals appears decorated with smaller crystallites that appear registered to the underlying crystal. b,c. High resolution images of well-aligned mithrene pillars.

We now turn to the measurements of emission color as a function of crystal morphology. Fluorescent images acquired through confocal microscopy in Figures 7a-7d show that all morphologies produce 467 nm emission. Figure 7a depicts the dominant, squarelike morphology of the mithrene crystal, the step edges of the layered chalcogenolate visible in the SEM image, and the uniform emission in the confocal micrograph. Although the crystalline products emit uniformly blue at 467 nm, highly distorted or defective crystals, such as those in Figure 7b and 7c, can sometimes produce populations of crystals that exhibit a redshift of ~5-10 nm. Additional companion high-resolution images of characteristic morphologies are collected in Figure S6. A 3D confocal map of crystals having the “rosette” or lenticular morphology are found in Figure S7. Although all preparations are robustly blue, normalized photoluminescence data of the most defective crystal populations reveals a small redshift and broadening of the emission. These comparisons for representative crystals can be found in Fig. S8. In other materials, this phenomenon is attributed to differences in defect density and modality, and we see evidence of such defect modes in the more distorted crystals observed at higher silver concentrations. Previous studies show a correlation between crystal thickness and photoluminescence properties in ordered organic semiconductors.77 Despite these small shifts, edge morphology control by modulation of crystal growth conditions presents an opportunity to engineer edge chemistry that may be suitable for post-synthetic modification.

In the case of surfactant-modified crystals, a distinct speckling pattern was evident. This is attributed to the pillar-like morphology found in those crystals, where the differences in intensity correspond with differences in thickness of the crystal (Figure 7d). This is consistent with the observation that crystal thickness is the primary contributor to emission intensity. Importantly, although many of the particles appeared smooth in the FESEM images, the speckling present in most crystallites confirms that most crystals were similarly modified by the pillar morphology. In summary, mithrene displays robust photoluminescence within the same range of emission wavelength despite significant morphology changes induced by adjusting growth conditions. Crystal Structure is Conserved across All Morphologies Biphasic synthesis is a straightforward method for screening a wide variety of reaction conditions, but the characteristically low yield of crystals is generally incompatible with the larger amounts of sample required for powder X-ray diffraction (pXRD) using a laboratory source. For example, to obtain enough material for pXRD, we combined the products from 50 individual reactions. Although the number of crystals isolated by the interfacial assembly method is low, the high flux of the focused incident beam produced by a synchrotron light source enables a straightforward characterization of the product’s crystallographic phase. First, we present the 1D profiles showing the high ordering of the monoclinic crystalline phase. Second, we show the 2D GIWAXS images to illustrate amorphous halos from the polymer byproduct, preferential alignment of crystals within the films, and some Debye-Scherrer rings from more randomly oriented powder-like films. The 1D profiles are collected in Figure 8.



Figure 8. a. 1D radial average profile of bulk powder as a comparison to subsequent crystalline samples. The bulk powder was prepared by isolating the films from ~50 samples prepared at concentrations of 3 mM/3mM silver nitrate and DPSe. We found no evidence for multiple crystalline phases. The 2D image that corresponds with this plot can be seen in the supplemental. b. 1D radial average profiles of samples of silver nitrate conditions from 0.5 mM to 10 mM at 3 days of growth. c.1D radial average profiles of samples at 5 days of growth show peak broadening and smoothing in the 5 mM profile but not as evident in the 10 mM profile . The {008} peak in the 10 mM profile is barely evident. d. 1D radial average profiles of crystalline samples at 10 days of growth.

Figure 8a shows the result from a well-mixed bulk preparation of mithrene (2D GIWAXS image found in Fig. S9). Previously determined lattice parameters as reported by Cuthbert et al. were used to verify assignments.18 Intense Bragg scattering reflections have been indexed as the {002}, {004}, {006}, {008}, and {0010} crystallographic planes, which correspond with the lamellar stacking of the silver-selenium monolayer of the material. The three most intense peaks correspond with the {002}, {004}, and {006} crystallographic planes of the silver benzeneselenolate unit cell. All samples show strong peaks at these representative q scattering vector values that correspond with the preferred face-on orientation of the material. Evidence of strain in the crystal structure at higher concentrations of silver is seen by peak broadening and smoothing of the 1D profiles in Fig. 8b-8d. Peak splitting at {006} can be seen in the 10 mM profile. Peak broadening and smoothing of all indexed peaks at 10 mM and 5 mM as compared to 0.5 mM and 1.5 mM can be seen at 3 days of growth. Initial peak splitting seen in the {006} peak of the 10 mM profile is still present but has a pronounced shoulder as opposed to equal splitting. The 5 mM profile shows significant evidence of smoothing and peak broadening, the corresponding 2D GIWAXS image shows smearing of the scattering rods associated with the main diffraction peaks and an evident amorphous halo at 1.0 q. The 1.5 mM profile also shows some smoothing at the {008) and {0010} peaks. Radial average profiles of crystalline film samples at 10 days of growth show significant peak broadening and smoothing in the 10 mM profile in which the higher q reflections {008) and {0010} are not seen. The 5 mM profile is available in the supplemental and shows some peak broadening. Percentages of strain in the 5mM silver nitrate sample can be computed by a comparison to a bulk powder sample of the standard square crystallites.78 It should be noted that even with strain present in these morphologies, the emission spectra of these crystals remain within the same wavelength range as the square shaped crystals.

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cell as identified in the radial 1D profiles (Fig. 9). This correlates with the preferred face-on orientation of the mithrene crystallites in the films, in which the {001} face is parallel to the substrate. Low-intensity reflections in the out-ofplane qxy can be seen, and have been indexed as {111}, {116}, and {202}. Although mithrene shows preferred face-on orientation, because of the topography of the MOCP and physical deformation during harvesting, shifts in orientation are forced, creating these texturing reflections. In Figure 9c-9e, amorphous halos are present at approximately 1.5 q which correspond with increased presence of the MOCP at higher concentrations of silver nitrate and longer growth times. Debye-Scherrer ring and smearing presence show evidence of more randomly oriented crystallites in the higher silver nitrate concentrations. This observation corresponds with the changes in crystal habit also shifting preferred orientation in some cases. In Figure 9c, the {008} and {0010} peaks cannot be resolved in the 2D GIWAXS images, which could be attributed to relative abundance of lenticular crystallites (see Figs. 7b) in that sample, or to a lower degree of order. Across all samples, there are no significant shifts in scattering peak q position that would imply formation of new phases. No phase changes occur in any of the concentrations examined and the crystal lattice of mithrene stays the same regardless of crystal habit. In Figure 10, 2D images of crystallites grown in lower silver concentrations show predominantly face-on preferred orientation of the basal plane in contact with the substrate, but there is some Debye-Scherrer smearing associated with random orientation in Figures 10a and 10b. Notably, the out-of-plane reflections (e.g. {111}, {116} and {202}) are present due to this non-uniformity in orientation, and are seen in Figures 10b-10f. Even with these noted shifts in texture and orientation, scattering peak q positions do not shift, as lower concentrations of silver nitrate do not affect crystal structure. Ewald sphere corrections for all 2D GIWAXS images are presented in the supplementary information, Figs. S11 and S12.

Figure 9. a-c. 2D GIWAXS patterns of crystallites grown at high concentrations of silver for 3, 5, and 10 days. Intense diffraction features have been indexed as the {002}, {004}, {006}, {008}, and {0010} crystallographic planes of mithrene are seen in the qz plane, which corresponds with the preferred face-on orientation of mithrene crystallites. c. Relative weakness of the {008} and {0010} peaks is attributed to sparse crystallite coverage or crystallographic strain. d-f. 2D GIWAXS images of crystallites grown in 5 mM silver for 3, 5, and 10 days. Crystals primarily adopt a face-on orientation, but the powder-like diffraction rings are evident of a nearly random orientation.

2D GIWAXS images of crystals grown at high concentrations of silver nitrate show high intensity diffraction peaks in the qz coordinate plane that correspond with the {002}, {004}, {006}, {008}, and {0010} crystallographic planes of the mithrene unit


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ACS Applied Nano Materials analysis of biological and chemical species ranging from detection of diseases to screening of new drug compounds.80 Although the semiconducting properties of mithrene were found to be generally robust in this example, our straightforward method presents a template for interrogating fine-structural changes induced by experimental variables and their relationship to crystal morphology and optoelectronic, catalytic, or gas absorptive properties. Crystal habit modification of hybrid low-dimensional compounds present a straightforward route towards optimization of surface and step-edge area of periodic nanostructured materials. This enables a direct route towards controlling accessibility for postsynthetic modification. For example, mithrene or other similar materials having a desired morphology might be functionalized after preparation for use in applications, such as biosensors or optoelectronic devices.

Figure 10. a-c. 2D GIWAXS patterns of crystallites grown at 1.5 mM and d-f. 0.5 mM silver nitrate. Crystals are predominantly orientated faceon with respect to the substrate. Debye-Scherrer smearing associated with increasing orientation randomness are observed in some samples, notably a. and b. Deviation from the face-on orientation is evident with the emergence of features associated with the {111}, {116}, and {202} reflections due to shifts in orientation of the crystals attributed to texturing of the product layers.

Conclusions Crystalline, blue-luminescent mithrene (silver benzeneselenolate) evolves at immiscible liquid-liquid interfaces. Although the crystal morphology is sensitive to the concentration of the silver nitrate reagent, there was no systematic link between the emission color and crystal habit or morphology. Acquisition of GIWAXS from sparse crystalline films using the high-flux incident beam produced by the synchrotron enabled positive identification of crystallographic phase and orientation without scaling the reaction up to bulk quantities. Even at extremely low-crystal-coverage, the characteristic peaks associated with the basal plane were straightforward to identify, and crystal structure was conserved across all morphologies. The blue photoluminescence of the mithrene crystal is a reliable proxy for the mithrene crystal structure. High silver nitrate concentrations are linked to extension at the {010} and {100} crystal facets. Distortion of the crystal morphology occurred at these concentrations, attributed to deformation of the crystal at the liquid-liquid interface as the crystal grew in these lateral directions. Abundant silver nitrate promoted growth of an amorphous MOCP, a silver-rich amorphous polymer phase. The matrix-like morphology of this side-product serves to spatially entrap crystallites for convenient harvest and subsequent characterization. Additionally, other than contributing the halo associated with amorphous materials and diffuse scattering at low q ranges, the amorphous phase contributed no identifiable reflections to the spectrum and no assignment of scattering peaks could be made. Additionally, the presence of CTAB surfactant was shown to impact crystallite growth in the {001} facet. We found the GIWAXS method of analysis of crystal structure a convenient approach for examining crystallization variables for the biphasic liquid-liquid reactions. This method can be applied broadly to examine any such low-yield reactions that do not lend themselves to pXRD or to single crystal X-ray diffraction, and may be of particular interest in the fields of other hybrid systems including MOFs and metal-halide perovskites. Coupling the GIWAXS technique developed here to high-throughput synthetic approaches would be particularly fruitful for screening libraries of hybrid materials and reaction conditions to automate material discovery and optimization.79

After identifying the role of precursor concentration on crystal habit, determining how to decouple the nucleation and growth reactions of these and related materials is a natural next step.81 To overcome both instrument limitations and synthetic route compatibility, we have implemented the use of high throughput solution small-angle X-ray scattering to probe the growth mechanism of mithrene. The results from these experiments will be reported in a follow up manuscript that will provide a necessary blueprint for future characterization of other similar material systems. MATERIALS AND METHODS MATERIALS Silver nitrate (>99%), diphenyl diselenide (98%), and CTAB (98%) were used as received by Sigma Aldrich (St. Louis, MO) and TCI America (Portland, OR). Toluene was used as received by EMD Millipore (Hayward, CA). 18.2 MΩ water was supplied by a Milli-Q system by Millipore (Billerica, MA). Glass scintillation vials were purchased from Thomas Scientific (24-400). Silicon substrates for sample collection were cleaved from 525 µm thick p-type silicon wafers from University Wafers (Boston, MA). METHODS Solutions of diphenyl diselenide and silver nitrate were prepared volumetrically in toluene and water, respectively, to the desired concentrations. Three milliliters of the aqueous silver nitrate solution were pipetted into a 20 mL glass vial. Three milliliters of the toluene DPSe solution were subsequently pipetted atop the aqueous solution to yield an immiscible liquid-liquid interface. The vial was capped and allowed to rest on the benchtop for the desired time. Samples were protected from direct sunlight, but incidental exposure to laboratory light was not controlled. Care should be taken when selecting the cap employed to ensure chemical compatibility between the toluene and cap material. We found that low-density polyethylene cone liners are not compatible after long exposure to the toluene vapor, and can contaminate the reaction. Solutions of aqueous silver nitrate and diphenyl diselenide in toluene were prepared in the range of 0.5-10 mM. One reagent was varied while the other was held uniform at 3 mM to identify which reagent played a role in crystal morphology. Three identical samples of each combination were allowed to crystallize undisturbed, and each were harvested at 3 days, 5 days, and 10 days. Surfactant experiments were designed to test the effects of CTAB on crystal nucleation and growth. Initial solution of 0.5 mM CTAB was prepared and diluted up to 5.0x10-4 mM CTAB prior to being layered on aqueous silver nitrate. Diphenyl diselenide in toluene was added at standard concentration per the immiscible interface synthesis.

Nanostructured materials continue to be of interest in the development of new sensing tools that enable direct and sensitive



CRYSTAL HARVESTING Silicon substrates were first cleaned with compressed air to remove any loose surface particles. The solid precipitate was harvested from each glass vial by first passing a vertically oriented polished silicon substrate through the organic layer and into the aqueous layer phase using tweezers. The sample was then tilted to a ~45º angle and raised through the interface, and withdrawn from the vial. The solid film remains adherent to the wafer. Gentle drying by forced air removed residual solvent, leaving crystals adhered to the silicon substrate. Once dried, a gentle rinse with isopropanol removed any solvent and associated precursors that had dried on the surface of the crystalline films. Using this same method of harvesting the CTAB modified mithrene crystals proved to be ineffective because decreased water surface tension that prevented the crystals from adsorbing onto the silicon substrate. To isolate these crystals, the aqueous layer was first pipetted out. The crystals were adsorbed to the glass surface, and the organic layer was decanted. Addition of isopropyl alcohol followed by sonication yielded a suspension of the crystals, which could be drop-casted onto the substrate. Isolating bulk crystal samples for pXRD was performed by preparing many reactions in parallel. The aqueous layer was first pipetted out. The vial was swirled, causing the precipitate to adhere to the glass. The toluene was then decanted. 5 mL Isopropanol was added to a reaction, and brief sonication suspended the crystals. This solution was then transferred to the next vial, and sonicated again. This bulked product was then isolated by ultracentrifugation and decanting of the isopropanol. CHARACTERIZATION Morphologies of the crystals at different experimental conditions were characterized using scanning electron microscopy (SEM) on a FEI Phenom ProX Tabletop SEM at accelerating voltages of 5 or 15 kV. Additional high-resolution SEM images were collected using a Zeiss Gemini Ultra-55 Analytical Field Emission SEM with an electron accelerating voltages of 1-3 kV. Complementary confirmation of composition was performed using EDS. An accelerating voltage of 5-10 kV was sufficient to confirm the 1:1 silver-selenium ratio for the mithrene crystals and 2:1 silver-selenium ratio for the MOCP. Fluorescent images were acquired on a Zeiss LSM 710 confocal microscope with an Axio Observer.Z1 (Carl Zeiss Microimaging, Thornwood, NY). Samples of product was harvested on glass coverslips (No. 1.5) and imaged using a 100× oil immersion objective (Plan-Apochromat, 1.40 NA). Confocal scans of the material were obtained using a 405 nm laser diode to excite the sample and a 585 µm wide pinhole. The emission spectrum was separated and the intensity of light between 400-700 nm (in 10 nm bins) was recorded on 32 detectors using the LSM 710 Linear Unmixing mode. The 32 images were imported to and analyzed using FIJI.82 Isolated crystals were defined using the tracing tool in FIJI to detect the edges of the single crystal and then used create a region of interest (ROI) around the crystal. For each ROI, the mean intensity, area, width and height was measured and recorded. Data was then exported to Origin 8.5.1 (Originlab, Northampton, MA) for analysis by linear regression and plotting. Grazing incidence wide angle X-ray scattering (GIWAXS) measurements were carried out at beamline 7.3.3 at the Advanced Light Source, Lawrence Berkeley National Laboratory.83-84 The bend beamline was operated at an energy of 10 keV. 2dimensional images were collected using CCD area detectors with a pixel size of 172 µm. The beam size was 0.5 mm. Sampledetector distance was 280 mm. Sample measurements were carried out in helium atmosphere on a grazing incidence static stage. The patterns were calibrated using a standard silver behenate powder sample on silicon substrate.85 2D Data reduction was performed using the Nika 2D data reduction package86 (Advanced

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Photon Source, Argonne National Laboratory) for Igor Pro (Wavemetrics Inc.). Ewald sphere corrections were performed using Xi-cam I.87 Using the experimental refined lattice parameters from Cuthbert et al.18 with the reciprocal-space metric tensor equation, the GIWAXS data was indexed with respect to the 1.24 Å wavelength at the beamline to identify the most intense peaks in the linecut plots and 2D images.

ASSOCIATED CONTENT Supporting Information The supporting information is available free of charge on the ACS Publications website. S1, S2 Calculated PXRD spectra (2θ and q x-axis). S3 High resolution imaes of MOCP coevolved with mithrene crystals. S4 EDS report of MOCP matrix, S5 SEM micrographs of crystallites grown in modified diphenyl diselenide conditions, S6: High resolution SEM images of morphologies of mithrene crystals. S7 3D rendering fluorescent image of crystallites grown in 10 mM Ag conditions for 3 days, S8 photoluminescence spectra of defective mithrene crystallites grown in 5 mM Ag conditions for 5 days, S9 2D GIWAXS image of isotropic bulk mithrene powder, S10 GIWAXS 1D Radial profile of 5 mM Ag conditions crystallites, S11,S12 2D GIWAXS images corrected for Ewald sphere.

AUTHOR INFORMATION Corresponding Author E-mail: [email protected]

Author Contributions The experiments were conceived and designed by EAS and JNH, and were executed and analyzed by EAS, DCP, MY, and JNH. Experiments at the synchrotron were performed by EAS and MAB. The manuscript was written through contributions from all authors.

Notes The authors declare no competing financial interest.

ACKNOWLEDGMENT This research used resources of beamline 7.3.3 at the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DE-AC02-05CH1123. These authors acknowledge beamline staff members, C.Z. and A.L.P. at beamline 7.3.3 for their assistance in data collection. Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The authors warmly acknowledge Dr. David Prendergast for helpful discussions and Dr. Behzad Rad for microscopy support.

ABBREVIATIONS MOCHA, metal-organic chalcogenolate assembly; MOF, metal-organic framework; DPSe, diphenyl diselenide; CTAB, Cetytrimeythylammonium bromide; MOCP, metal-organic coordination polymer; SEM, Scanning Electron Microscopy; FESEM, field emission scanning electron microscopy; EDS, energydispersive X-ray spectroscopy; GIWAXS, grazing incidence wide angle X-ray scattering.


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REFERENCES

1. Mak, K. F.; Lee, C.; Hone, J.; Shan, J.; Heinz, T. F. Atomically Thin MoS2: A New Direct-Gap Semiconductor. Phys. Rev. Lett. 2010, 105, 136805. 2. Radisavljevic, B.; Radenovic, A.; Brivio, J.; Giacometti, V.; Kis, A. Single-Layer MoS2 Transistors. Nat. Nanotechnol. 2011, 6, 147-150. 3. Huang, Y.; Dong, X.; Liu, Y.; Li, L.-J.; Chen, P. Graphene-Based Biosensors for Detection of Bacteria and their Metabolic Activities. J. Mater. Chem. 2011, 21, 12358-12362. 4. Achtstein, A. W.; Schliwa, A.; Prudnikau, A.; Hardzei, M.; Artemyev, M. V.; Thomsen, C.; Woggon, U. Electronic Structure and Exciton--Phonon Interaction in Two-Dimensional Colloidal CdSe Nanosheets. Nano Lett. 2012, 12, 3151-3157. 5. Britnell, L.; Ribeiro, R. M.; Eckmann, A.; Jalil, R.; Belle, B. D.; Mishchenko, A.; Kim, Y. J.; Gorbachev, R. V.; Georgiou, T.; Morozov, S. V.; Grigorenko, A. N.; Geim, A. K.; Casiraghi, C.; Neto, A. H. C.; Novoselov, K. S. Strong Light-Matter Interactions in Heterostructures of Atomically Thin Films. Science 2013, 340, 1311-1314. 6. Kunneman, L. T.; Tessier, M. D.; Heuclin, H.; Dubertret, B.; Aulin, Y. V.; Grozema, F. C.; Schins, J. M.; Siebbeles, L. D. A. Bimolecular Auger Recombination of Electron--Hole Pairs in TwoDimensional CdSe and CdSe/CdZnS Core/Shell Nanoplatelets. J. Phys. Chem. Lett. 2013, 4, 35743578. 7. Wang, H.; Yu, L.; Lee, Y.-H.; Shi, Y.; Hsu, A.; Chin, M. L.; Li, L.-J.; Dubey, M.; Kong, J.; Palacios, T. Integrated Circuits Based on Bilayer MoS2 Transistors. Nano Lett. 2013, 12, 4674-4680. 8. Kim, W.-g.; Nair, S. Membranes from Nanoporous 1D and 2D Materials: A Review of Opportunities, Developments, and Challenges. Chem. Eng. Sci. 2013, 104, 908-924. 9. Miro, P.; Audiffred, M.; Heine, T. An Atlas of Two-Dimensional Materials. Chem. Soc. Rev. 2014, 43, 6537-6554. 10. Voiry, D.; Goswami, A.; Kappera, R.; Silva, C. d. C. C. e.; Kaplan, D.; Fujita, T.; Chen, M.; Asefa, T.; Chhowalla, M. Covalent Functionalization of Monolayered Transition Metal Dichalcogenides by Phase Engineering. Nature Chem. 2014, 7, 45. 11. Bhimanapati, G. R.; Lin, Z.; Meunier, V.; Jung, Y.; Cha, J.; Das, S.; Xiao, D.; Son, Y.; Strano, M. S.; Cooper, V. R.; Liang, L.; Louie, S. G.; Ringe, E.; Zhou, W.; Kim, S. S.; Naik, R. R.; Sumpter, B. G.; Terrones, H.; Xia, F.; Wang, Y.; Zhu, J.; Akinwande, D.; Alem, N.; Schuller, J. A.; Schaak, R. E.; Terrones, M.; Robinson, J. A. Recent Advances in Two-Dimensional Materials beyond Graphene. ACS Nano 2015, 9, 11509-11539. 12. Liu, Z.; Lau, S. P.; Yan, F. Functionalized Graphene and Other Two-Dimensional Materials for Photovoltaic Devices: Device Design and Processing. Chem. Soc. Rev. 2015, 44, 5638-5679. 13. Jung, Y.; Zhou, Y.; Cha, J. J. Intercalation in Two-Dimensional Transition Metal Chalcogenides. Inorg. Chem. Front. 2016, 3, 452-463. 14. Chen, Y. C.; Lu, A. Y.; Lu, P.; Yang, X.; Jiang, C. M.; Mariano, M.; Kaehr, B.; Lin, O.; Taylor, A.; Sharp, I. D.; Li, L. J.; Chou, S. S.; Tung, V. Structurally Deformed MoS2 for Electrochemically Stable, Thermally Resistant, and Highly Efficient Hydrogen Evolution Reaction. Adv. Mater. 2017, 29, 1703863. 15. Judeinstein, P.; Sanchez, C. Hybrid Organic-Inorganic Materials: a Land of Multidisciplinarity. J. Mater. Chem. 1996, 6, 511-525. 16. Huang, X.; Li, J.; Fu, H. The First Covalent Organic−Inorganic Networks of Hybrid Chalcogenides: Structures That May Lead to a New Type of Quantum Wells. J. Am. Chem. Soc. 2000, 122, 8789-8790. 17. Huang, X.; Heulings; Le, V.; Li, J. Inorganic−Organic Hybrid Composites Containing MQ (II−VI) Slabs: A New Class of Nanostructures with Strong Quantum Confinement and Periodic Arrangement. Chem. Mater. 2001, 13, 3754-3759.


9


Page 10 of 14

18. Cuthbert, H. L.; Wallbank, A. I.; Taylor, N. J.; Corrigan, J. F. Synthesis and Structural Characterization of [Cu20Se4(µ3-SePh)12(PPh3)6] and [Ag(SePh)]∞. Z. Anorg. Allg. Chem. 2002, 628, 2483-2488. 19. Janiak, C. Engineering coordination polymers towards applications. Dalton Trans. 2003, 27812804. 20. Hu, L.; Zhang, Z.; Zhang, M.; Efremov, M. Y.; Olson, E. A.; de la Rama, L. P.; Kummamuru, R. K.; Allen, L. H. Self-Assembly and Ripening of Polymeric Silver−Alkanethiolate Crystals on Inert Surfaces. Langmuir 2009, 25, 9585-9595. 21. de la Rama, L. P.; Hu, L.; Ye, Z.; Efremov, M. Y.; Allen, L. H. Size Effect and Odd–Even Alternation in the Melting of Single and Stacked AgSCn Layers: Synthesis and Nanocalorimetry Measurements. J. Am. Chem. Soc. 2013, 135, 14286-14298. 22. Wang, S.; Li, J. Two-Dimensional Inorganic–Organic Hybrid Semiconductors Composed of Double-Layered ZnS and Monoamines with Aromatic and Heterocyclic Aliphatic Rings: Syntheses, Structures, and Properties. J. Solid State Chem. 2014, 23. Luo, J.; Gao, J.; Wang, A.; Huang, J. Bulk Nanostructured Materials Based on TwoDimensional Building Blocks: A Roadmap. ACS Nano 2015, 9, 9432-9436. 24. Ye, Z.; Rama, L. P. d. l.; Y. Efremov, M.; Zuo, J.-M.; H. Allen, L. Approaching the Size Limit of Organometallic Layers: Synthesis and Characterization of Highly Ordered Silver–Thiolate Lamellae with Ultra-Short Chain Lengths. Dalton Trans. 2016, 45, 18954-18966. 25. Yan, H.; Hohman, J. N.; Li, F. H.; Jia, C.; Solis-Ibarra, D.; Wu, B.; Dahl, J. E. P.; Carlson, R. M. K.; Tkachenko, B. A.; Fokin, A. A.; Schreiner, P. R.; Vailionis, A.; Kim, T. R.; Devereaux, T. P.; Shen, Z.-X.; Melosh, N. A. Hybrid Metal–Organic Chalcogenide Nanowires with Electrically Conductive Inorganic Core through Diamondoid-Directed Assembly. Nat. Mater. 2017, 16, 349-355. 26. Yan, H.; Yang, F.; Pan, D.; Lin, Y.; Hohman, J. N.; Solis-Ibarra, D.; Li, F. H.; Dahl, J. E. P.; Carlson, R. M. K.; Tkachenko, B. A.; Fokin, A. A.; Schreiner, P. R.; Galli, G.; Mao, W. L.; Shen, Z.-X.; Melosh, N. A. Sterically Controlled Mechanochemistry under Hydrostatic Pressure. Nature 2018, 554, 505. 27. Luo, X.; Morrin, A.; Killard, A. J.; Smyth, M. R. Application of Nanoparticles in Electrochemical Sensors and Biosensors. Electroanalysis 2006, 18, 319-326. 28. Allendorf, M. D.; Bauer, C. A.; Bhakta, R. K.; Houk, R. J. T. Luminescent Metal–Organic Frameworks. Chem. Soc. Rev. 2009, 38, 1330-1352. 29. Phan, A.; Doonan, C. J.; Uribe-Romo, F. J.; Knobler, C. B.; O’Keeffe, M.; Yaghi, O. M. Synthesis, Structure, and Carbon Dioxide Capture Properties of Zeolitic Imidazolate Frameworks. Acc. Chem. Res. 2010, 43, 58-67. 30. Lin, H.; Zhou, C.; Tian, Y.; Besara, T.; Neu, J.; Siegrist, T.; Zhou, Y.; Bullock, J.; S. Schanze, K.; Ming, W.; Du, M.-H.; Ma, B. Bulk Assembly of Organic Metal Halide Nanotubes. Chemical Science 2017, 8, 8400-8404. 31. Tongay, S.; Sahin, H.; Ko, C.; Luce, A.; Fan, W.; Liu, K.; Zhou, J.; Huang, Y.-S.; Ho, C.-H.; Yan, J.; Ogletree, D. F.; Aloni, S.; Ji, J.; Li, S.; Li, J.; Peeters, F. M.; Wu, J. Monolayer Behaviour in Bulk ReS2 due to Electronic and Vibrational Decoupling. Nat. Commun. 2014, 5, 3252. 32. Yuan, Z.; Zhou, C.; Tian, Y.; Shu, Y.; Messier, J.; Wang, J. C.; van de Burgt, L. J.; Kountouriotis, K.; Xin, Y.; Holt, E.; Schanze, K.; Clark, R.; Siegrist, T.; Ma, B. One-Dimensional Organic Lead Halide Perovskites with Efficient Bluish White-Light Emission. Nat. Commun. 2017, 8, 14051. 33. Solis-Ibarra, D.; Smith, I. C.; Karunadasa, H. I. Post-Synthetic Halide Conversion and Selective Halogen Capture in Hybrid Perovskites. Chemical Science 2015, 6, 4054-4059. 34. Zhou, C.; Tian, Y.; Khabou, O.; Worku, M.; Zhou, Y.; Hurley, J.; Lin, H.; Ma, B. ManganeseDoped One-Dimensional Organic Lead Bromide Perovskites with Bright White Emissions. ACS Appl. Mater. Interfaces 2017, 35. Vargas, B.; Ramos, E.; Pérez-Gutiérrez, E.; Alonso, J. C.; Solis-Ibarra, D. A Direct Bandgap Copper–Antimony Halide Perovskite. J. Am. Chem. Soc. 2017, 139, 9116-9119. ACS Paragon Plus Environment

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Page 11 of 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


36. Kojima, A.; Teshima, K.; Shirai, Y.; Miyasaka, T. Organometal Halide Perovskites as VisibleLight Sensitizers for Photovoltaic Cells. J. Am. Chem. Soc. 2009, 131, 6050-6051. 37. Talin, A. A.; Centrone, A.; Ford, A. C.; Foster, M. E.; Stavila, V.; Haney, P.; Kinney, R. A.; Szalai, V.; El Gabaly, F.; Yoon, H. P.; Léonard, F.; Allendorf, M. D. Tunable Electrical Conductivity in Metal-Organic Framework Thin-Film Devices. Science 2014, 343, 66-69. 38. Stoumpos, C. C.; Kanatzidis, M. G. The Renaissance of Halide Perovskites and Their Evolution as Emerging Semiconductors. Acc. Chem. Res. 2015, 48, 2791-2802. 39. Corrigan, J. F.; Fenske, D.; Power, W. P. Silver-Tellurolate Polynuclear Complexes: From Isolated Cluster Units to Extended Polymer Chains. Angew. Chem., Int. Ed. 1997, 36, 1176-1179. 40. Bensebaa, F.; Ellis, T. H.; Kruus, E.; Voicu, R.; Zhou, Y. Characterization of self-assembled bilayers: Silver-alkanethiolates. Langmuir 1998, 14, 6579-6587. 41. Hu, L.; Zhang, Z.; Zhang, M.; Efremov, M. Y.; Olson, E. A.; de la Rama, L. P.; Kummamuru, R. K.; Allen, L. H. Self-Assembly and Ripening of Polymeric Silver-Alkanethiolate Crystals on Inert Surfaces. Langmuir 2009, 25, 9585-9595. 42. Corrigan, J. F.; Fuhr, O.; Fenske, D. Metal Chalcogenide Clusters on the Border between Molecules and Materials. Adv. Mater. 2009, 21, 1867-1871. 43. de la Rama, L. P.; Hu, L.; Ye, Z.; Efremov, M. Y.; Allen, L. H. Size Effect and Odd-Even Alternation in the Melting of Single and Stacked AgSCn Layers: Synthesis and Nanocalorimetry Measurements. J. Am. Chem. Soc. 2013, 135, 14286-14298. 44. Low, K.-H.; Li, C.-H.; Roy, V. A. L.; Chui, S. S.-Y.; Chan, S. L.-F.; Che, C.-M. Homoleptic Copper(I) Phenylselenolate Polymer as a Single-source Precursor for Cu2Se Nanocrystals. Structure, Photoluminescence and Application in Field-Effect Transistor. Chemical Science 2010, 1, 515-518. 45. Lavenn, C.; Guillou, N.; Monge, M.; Podbevsek, D.; Ledoux, G.; Fateeva, A.; Demessence, A. Shedding Light on an Utra-Bight Photoluminescent Lamellar Gold Thiolate Coordination Polymer [Au(p-SPhCO2Me)]n. Chem. Commun. 2016, 52, 9063-9066. 46. Yan, H.; Hohman, J. N.; Li, F. H.; Jia, C.; Solis-Ibarra, D.; Wu, B.; Dahl, J. E. P.; Carlson, R. M. K.; Tkachenko, B. A.; Fokin, A. A.; Schreiner, P. R.; Vailionis, A.; Kim, T. R.; Devereaux, T. P.; Shen, Z.-X.; Melosh, N. A. Hybrid metal-organic chalcogenide nanowires with electrically conductive inorganic core through diamondoid-directed assembly. Nat. Mater. 2017, 16, 349-355. 47. Veselska, O.; Demessence, A. d10 Coinage Metal Organic Chalcogenolates: From Oligomers to Coordination Polymers. Coord. Chem. Rev. 2018, 355, 240-270. 48. Mo, M.-s.; Shao, M.-w.; Hu, H.-m.; Yang, L.; Yu, W.-c.; Qian, Y.-t. Growth of single-crystal PbS nanorods via a biphasic solvothermal interface reaction route. J. Cryst. Growth 2002, 244, 364-368. 49. Forster, P. M.; Thomas, P. M.; Cheetham, A. K. Biphasic Solvothermal Synthesis: A New Approach for Hybrid Inorganic−Organic Materials. Chem. Mater. 2002, 14, 17-20. 50. Ameloot, R.; Vermoortele, F.; Vanhove, W.; Roeffaers, M. B. J.; Sels, B. F.; Vos, D. E. D. Interfacial synthesis of hollow metal–organic framework capsules demonstrating selective permeability. Nature Chem. 2011, 3, 382-387. 51. Inoue, S.; Fujihara, S. Liquid−Liquid Biphasic Synthesis of Layered Zinc Hydroxides Intercalated with Long-Chain Carboxylate Ions and Their Conversion into ZnO Nanostructures. Inorg. Chem. 2011, 50, 3605-3612. 52. Martínez-Máñez, R.; Sancenón, F.; Hecht, M.; Biyikal, M.; Rurack, K. Nanoscopic Optical Sensors Based on Functional Supramolecular Hybrid Materials. Anal. Bioanal. Chem. 2011, 399, 55-74. 53. Duan, X.; Huang, Y.; Cui, Y.; Wang, J.; Lieber, C. M. Indium Phosphide Nanowires as Building Blocks for Nanoscale Electronic and Optoelectronic Devices. Nature 2001, 409, 66-69. 54. Fu, Y.; Li, P.; Bu, L.; Wang, T.; Xie, Q.; Chen, J.; Yao, S. Exploiting Metal-Organic Coordination Polymers as Highly Efficient Immobilization Matrixes of Enzymes for Sensitive Electrochemical Biosensing. Anal. Chem. 2011, 83, 6511-6517. 55. Peng, X.; Manna, L.; Yang, W.; Wickham, J.; Scher, E.; Kadavanich, A.; Alivisatos, A. P. Shape Control of CdSe Nanocrystals. Nature 2000, 404, 59-61. ACS Paragon Plus Environment

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Page 12 of 14

56. Farha, O. K.; Spokoyny, A. M.; Mulfort, K. L.; Galli, S.; Hupp, J. T.; Mirkin, C. A. GasSorption Properties of Cobalt(II)–Carborane-Based Coordination Polymers as a Function of Morphology. Small 2009, 5, 1727-1731. 57. Jo, C.; Jung, J.; Shin, H. S.; Kim, J.; Ryoo, R. Capping with Multivalent Surfactants for Zeolite Nanocrystal Synthesis. Angew. Chem., Int. Ed. 2013, 52, 10014-10017. 58. Sarang, S.; Bonabi Naghadeh, S.; Luo, B.; Kumar, P.; Betady, E.; Tung, V.; Scheibner, M.; Zhang, J. Z.; Ghosh, S. Stabilization of the Cubic Crystalline Phase in Organometal Halide Perovskite Quantum Dots via Surface Energy Manipulation. J. Phys. Chem. Lett. 2017, 8, 5378-5384. 59. Liu, G.; Yu, J. C.; Lu, G. Q. M.; Cheng, H.-M. Crystal Facet Engineering of Semiconductor Photocatalysts: Motivations, Advances and Unique Properties. Chem. Commun. 2011, 47, 6763-6783. 60. Li, H.; Eddaoudi, M.; O'Keeffe, M.; Yaghi, O. M. Design and Synthesis of an Exceptionally Stable and Highly Porous Metal-Organic Framework. Nature 1999, 402, 276-279. 61. Yaghi, O. M.; O'Keeffe, M.; Ockwig, N. W.; Chae, H. K.; Eddaoudi, M.; Kim, J. Reticular Synthesis and the Design of New Materials. Nature 2003, 423, 705-714. 62. Kumar, R.; Jayaramulu, K.; Kumar Maji, T.; R. Rao, C. N. Hybrid Nanocomposites of ZIF-8 with Graphene Oxide Exhibiting Tunable Morphology, Significant CO2 Uptake and Other Novel Properties. Chem. Commun. 2013, 49, 4947-4949. 63. Tang, J.; Yamauchi, Y. Carbon Materials: MOF Morphologies in Control. Nature Chem. 2016, 8, 638-639. 64. Li, R.; Smolyakova, A.; Maayan, G.; Rimer, J. D. Designed Peptoids as Tunable Modifiers of Zeolite Crystallization. Chem. Mater. 2017, 29, 9536-9546. 65. Chawla, A.; Li, R.; Jain, R.; Clark, R. J.; Sutjianto, J. G.; Palmer, J. C.; Rimer, J. D. Cooperative Effects of Inorganic and Organic Structure-Directing Agents in ZSM-5 Crystallization. Mol. Syst. Des. Eng. 2018, 3, 159-170. 66. Zhang, G.; Sun, S.; Banis, M. N.; Li, R.; Cai, M.; Sun, X. Morphology-Controlled Green Synthesis of Single Crystalline Silver Dendrites, Dendritic Flowers, and Rods, and Their Growth Mechanism. Cryst. Growth Des. 2011, 11, 2493-2499. 67. Yadav, H.; Sinha, N.; Kumar, B. New Geometrical Modeling To Study Crystal Morphology. Cryst. Growth Des. 2016, 16, 4559-4566. 68. Pan, D.; Liu, L.-M.; Slater, B.; Michaelides, A.; Wang, E. Melting the Ice: On the Relation between Melting Temperature and Size for Nanoscale Ice Crystals. ACS Nano 2011, 5, 4562-4569. 69. Heidorn, S.-C.; Bertram, C.; Morgenstern, K. The Fractal Dimension of Ice on the Nanoscale. Chem. Phys. Lett. 2016, 665, 1-5. 70. Christner, B. C.; Cai, R.; Morris, C. E.; McCarter, K. S.; Foreman, C. M.; Skidmore, M. L.; Montross, S. N.; Sands, D. C. Geographic, Seasonal, and Precipitation Chemistry Influence on the Abundance and Activity of Biological Ice Nucleators in Rain and Snow. Proc. Natl. Acad. Sci. U. S. A. 2008, 105, 18854. 71. J. Cox, S.; Raza, Z.; M. Kathmann, S.; Slater, B.; Michaelides, A. The Microscopic Features of Heterogeneous Ice Nucleation may Affect the Macroscopic Morphology of Atmospheric Ice Crystals. Faraday Discuss. 2013, 167, 389-403. 72. Petzold, G.; Aguilera, J. M. Ice Morphology: Fundamentals and Technological Applications in Foods. Food Biophysics 2009, 4, 378-396. 73. Zheng, G.; Chen, Z.; Sentosun, K.; Pérez-Juste, I.; Bals, S.; Liz-Marzán, L. M.; PastorizaSantos, I.; Pérez-Juste, J.; Hong, M. Shape Control in ZIF-8 Nanocrystals and Metal Nanoparticles@ZIF-8 Heterostructures. Nanoscale 2017, 9, 16645-16651. 74. Li, B.; Jiang, B.; Tang, H.; Lin, Z. Unconventional Seed-Mediated Growth of Ultrathin Au Nanowires in Aqueous Solution. Chemical Science 2015, 6, 6349-6354. 75. Smith, D. K.; Korgel, B. A. The Importance of the CTAB Surfactant on the Colloidal SeedMediated Synthesis of Gold Nanorods. Langmuir 2008, 24, 644-649. 76. Saien, J.; Asadabadi, S. Synergistic Adsorption of Triton X-100 and CTAB Surfactants at the Toluene+Water Interface. Fluid Phase Equilib. 2011, 307, 16-23. ACS Paragon Plus Environment

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77. Najafov, H.; Lee, B.; Zhou, Q.; C Feldman, L.; Podzorov, V. Observation of Long-Range Exciton Diffusion in Highly Ordered Organic Semiconductors. Nat. Mater. 2010, 9, 938-943. 78. Youn, J.; Kewalramani, S.; Emery, J. D.; Shi, Y.; Zhang, S.; Chang, H.-C.; Liang, Y.-j.; Yeh, C.M.; Feng, C.-Y.; Huang, H.; Stern, C.; Chen, L.-H.; Ho, J.-C.; Chen, M.-C.; Bedzyk, M. J.; Facchetti, A.; Marks, T. J. Fused Thiophene Semiconductors: Crystal Structure–Film Microstructure Transistor Performance Correlations. Adv. Funct. Mater. 2013, 23, 3850-3865. 79. Raccuglia, P.; Elbert, K. C.; Adler, P. D. F.; Falk, C.; Wenny, M. B.; Mollo, A.; Zeller, M.; Friedler, S. A.; Schrier, J.; Norquist, A. J. Machine-Learning-Assisted Materials Discovery using Failed Experiments. Nature 2016, 533, 73. 80. Patolsky, F.; Zheng, G.; Lieber, C. M. Nanowire Sensors for Medicine and the Life Sciences. Nanomedicine 2006, 1, 51-65. 81. Tanaka, M.; Yamanaka, S.; Shirakawa, Y.; Shimosaka, A.; Hidaka, J. Preparation of Porous Particles by Liquid-Liquid Interfacial Crystallization. Advanced Powder Technology 2011, 22, 125-130. 82. Schindelin, J.; Arganda-Carreras, I.; Frise, E.; Kaynig, V.; Longair, M.; Pietzsch, T.; Preibisch, S.; Rueden, C.; Saalfeld, S.; Schmid, B.; Tinevez, J.-Y.; White, D. J.; Hartenstein, V.; Eliceiri, K.; Tomancak, P.; Cardona, A. Fiji: an Open-Source Platform for Biological-Image Analysis. Nat. Methods 2012, 9, 676-682. 83. Hexemer, A.; Müller-Buschbaum, P. Advanced Grazing-Incidence Techniques for Modern SoftMatter Materials Analysis. IUCrJ 2015, 2, 106-125. 84. Hexemer, A.; Bras, W.; Glossinger, J.; Schaible, E.; Gann, E.; Kirian, R.; MacDowell, A.; Church, M.; Rude, B.; Padmore, H. A SAXS/WAXS/GISAXS Beamline with Multilayer Monochromator. J. Phys.: Conf. Ser. 2010, 247, 012007. 85. Huang, T. C.; Toraya, H.; Blanton, T. N.; Wu, Y. X-ray Powder Diffraction Analysis of Silver Behenate, a Possible Low-Angle Diffraction Standard. J. Appl. Crystallogr. 1993, 26, 180-184. 86. Ilavsky, J. Nika: Software for Two-Dimensional Data Reduction. J. Appl. Crystallogr. 2012, 45, 324-328. 87. Pandolfi, R. J.; Allan, D. B.; Arenholz, E.; Barroso-Luque, L.; Campbell, S. I.; Caswell, T. A.; Blair, A.; De Carlo, F.; Fackler, S.; Fournier, A. P.; Freychet, G.; Fukuto, M.; Gursoy, D.; Jiang, Z.; Krishnan, H.; Kumar, D.; Kline, R. J.; Li, R.; Liman, C.; Marchesini, S.; Mehta, A.; N'Diaye, A. T.; Parkinson, D. Y.; Parks, H.; Pellouchoud, L. A.; Perciano, T.; Ren, F.; Sahoo, S.; Strzalka, J.; Sunday, D.; Tassone, C. J.; Ushizima, D.; Venkatakrishnan, S.; Yager, K. G.; Zwart, P.; Sethian, J. A.; Hexemer, A. Xi-cam: a Versatile Interface for Data Visualization and Analysis. J. Synchrotron Radiat. 2018, 25, 1-4.


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Mithrene Is a Self-Assembling Robustly Blue Luminescent Metal

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