Microemulsion-Assisted Self-Assembly and Synthesis of Size

Subscriber access provided by ECU Libraries

Communication

Microemulsion-Assisted Self-Assembly and Synthesis of Size-Controlled Porphyrin Nanocrystals with Enhanced Photocatalytic Hydrogen Evolution Yanqiu Liu, Liang Wang, Hexiang Feng, Xitong Ren, Juanjuan Ji, Feng Bai, and Hongyou Fan Nano Lett., Just Accepted Manuscript • DOI: 10.1021/acs.nanolett.9b00423 • Publication Date (Web): 08 Mar 2019 Downloaded from http://pubs.acs.org on March 10, 2019

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 18 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

Nano Letters

Microemulsion-Assisted Self-Assembly and Synthesis of Size-Controlled Porphyrin Nanocrystals with Enhanced Photocatalytic Hydrogen Evolution Yanqiu Liu,1 Liang Wang,1Hexiang Feng,1 Xitong Ren,1 Juanjuan Ji,1 Feng Bai,1,* and Hongyou Fan2,3,4,* 1Key

Laboratory for Special Functional Materials of Ministry of Education, National

& Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China; 2Department of Chemical and Biological Engineering, Albuquerque, University of New

Mexico, Albuquerque, New Mexico 87106, United States; 3Center

for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque,

New Mexico 87185, United States; 4Advanced

Materials Laboratory, Sandia National Laboratories, Albuquerque, New

Mexico 87185, United States Corresponding author emails, phone numbers, and fax numbers: *F.B. ([email protected]), Tel: 86-15039024866, Fax: 86-0371-23883868 *H.F. ([email protected]), Tel: (505) 272-7128, Fax: (505) 272-7336 1

ACS Paragon Plus Environment

Nano Letters 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

ABSTRACT

Design and engineering of highly efficient light-harvesting nanomaterial systems to emulate natural photosynthesis for maximizing energy conversion have stimulated extensive efforts. Here we present a new class of photoactive semiconductor nanocrystals that exhibit high-efficiency energy transfer for enhanced photocatalytic hydrogen production under visible light. These nanocrystals are formed through noncovalent self-assembly of In(III) meso-tetraphenylporphine chloride (InTPP) during microemulsion (μ-emulsion) assisted nucleation and growth process. Through kinetic control, a series of uniform nanorods with controlled aspect ratio and high crystallinity have been fabricated. Self-assembly of InTPP porphyrins results in extensive optical coupling and broader coverage of visible spectrum for efficient light harvesting. As a result, these nanocrystals display excellent photocatalytic hydrogen production and photostability under the visible light in comparison with the commercial InTPP porphyrin powders.

KEYWORDS: Self-assembly, porphyrin, light-harvesting systems, photocatalytic hydrogen evolution, visible light.

2


Page 2 of 18

Page 3 of 18 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

Nano Letters

Design and construction of highly efficient light-harvesting systems have stimulated extensive efforts in developing methods to synthesize new photoactive materials. Of the variously possible strategies, nature provides a blueprint for solar-tochemical energy conversion, where the peculiar arrangement structure of chloroplasts in plants can tremendously promote the light-harvesting and energy transfer efficiency.1-6 However, precise engineering to acquire orderly arranged antenna chromophores is a great challenge. In recent years, with great potential for integrating all the molecular components and functions, molecular noncovalent self-assembly has considered to be an effective and economical route to construct novel ordered multifunctional materials.7-11 To date, through molecular self-assembly, a series of πconjugated molecules have been devoted to the synthesis of organic optoeletronic materials that have been extensively applied for luminescent devices, photovoltaics, and photocatalysts.12-15 Among them, porphyrin-based nanomaterials with well-defined and ordered structure can act as energy transfer scaffolds to simulate the natural lightharvesting systems.16-24 As a kind of natural pigments derived from plant and animal species, the outstanding optical characteristics and rigid planar molecular structure make porphyrins an ideal building block for synthesis of photoactive nanomaterials.25-29 In addition, the diversities of peripheral functional groups and central metal enable porphyrins to possess various properties and assembly modes.30-32 More importantly, the majority of porphyrin molecules own a suitable and reversible oxidization/reduction potential, which is an important feature of desired photocatalysts satisfying the

3


Nano Letters 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

thermodynamic factors of photo-driven water splitting. Despite of the advantages mentioned above, it is unfortunate that the porphyrin monomers exhibit a relative narrow absorption range in the visible light region and are susceptible to light corrosion. It has been proved that fine-tuning of intermolecular packing arrangement and noncovalent interactions (e.g., hydrogen bonding, π−π stacking, hydrophilic or hydrophobic interaction, ligand coordination, etc.) within the self-assembled porphyrin architectures can reduce the migration distance of charge carriers for enhanced photocatalytic activities.33-36 Also, the self-assembled porphyrin supramolecular system usually shows typical electronic structures of organic semiconductors with appropriate energy level. Therefore, owing to the availability of porphyrin species and long-range ordering structure, the controlled fabrication of porphyrin assemblies is a promising strategy for developing new and superior photocatalytic materials. Herein, we developed the synthesis of a new class of self-assembled porphyrin nanocrystals through noncovalent interactions during μ-emulsion confined nucleation and growth processes.37, 38 We used cetyltrimethylammonium bromide (CTAB) to form μ-emulsion to assist nucleation and growth of a commercial InTPP (Figure S1) as a molecular building block. Depending on the concentrations of CTAB, a series of high quality and crystalline InTPP nanorods were successfully synthesized. The ordered ππ stacking and long-range delocalization inside the porphyrin assemblies render these nanomaterials with tailored collective optical properties for broader visible light absorption spectrum. Additionally, they exhibit enhanced photocatalytic hydrogen evolution activities in comparison with the commercial InTPP porphyrin powders.

4


Page 4 of 18

Page 5 of 18 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

Nano Letters

Figure 1. Schematic illustration of formation process of the self-assembled InTPP nanostructures through an emulsion-based self-assembly process.

The porphyrin nanostructures were fabricated via an oil-in-water μ-emulsion assisted self-assembling process. As shown in Figure 1, an InTPP porphyrin chloroform solution was mixed with an aqueous solution of CTAB to form μ-emulsion via vigorous stirring or sonication. In the oil/water μ-emulsion medium, amphiphilic surfactants that act as a bridge between two separate phases (water and oil) promoted the formation of a homogeneous μ-emulsion. The μ-emulsion consisted of uniform oil-in-water droplets that serve as nanoreactors for confined nucleation and growth of InTPP porphyrin nanocrystals. When the μ-emulsion was subjected to given temperature (near or greater than the boiling point of the oil-phase or organic

5


Nano Letters 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

Figure 2. Self-assembled InTPP nanocrystals at different CTAB concentrations. Representative TEM images of the nanocrystals that were obtained at surfactant concentrations of (A) 2.5, (B) 10, (C) 15, and (D) 25 mM, respectively. (E) Statistic analysis curve of the average length and average diameter of the nanocrystals. (F) Simulated crystal structure from the XRD data, (Indium: bule, nitrogen: red, carbon: gray, chlorine: green). For clarafication, hydrogen atom is omitted.

6


Page 6 of 18

Page 7 of 18 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

Nano Letters

solvent), the organic solvent was volatilized. The evaporation of oil phase enriched the InTPP concentration within the μ-emulsion droplets and triggered the self-assembly of InTPP porphyrins into ordered nanocrystals through noncovalent interactions such as π-π stacking, hydrophobic-hydrophobic interactions. The final porphyrin nanocrystals were collected and purified by centrifugation for characterizations and hydrogen production studies. The morphology of the InTPP porphyrin nanocrystals, as a function of the CTAB concentrations, was investigated by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) imaging. Representative TEM (Figure 2A-D) and SEM (Figure S2A-D) images show that the resultant InTPP nanocrystals are uniform nanowires or nanorods. The monodispersity is confirmed by relatively narrow distribution of all nanocrystals by size statistics analysis (Figure S3). TEM images (Figure 2A-D) and corresponding statistical analysis curve (Figure 2E) show that welldefined nanowires or nanorods with controlled aspect ratio of 81.3, 21.0, 4.6, 1.6 can be obtained by tuning the surfactant concentrations. These results fully indicate that the surfactant concentrations play a key role in modulating the morphology and size of the nanocrystals. X-ray diffraction (XRD) analysis shows that the crystal structure of the InTPP porphyrin nanocrystals (Figure 3B) belongs to orthorhombic system with space group Pnna (52) and the unit cell dimension is a = 1.62 nm, b =1.00 nm, c = 2.11 nm, α = β = γ = 90˚. Corresponding crystal structure was simulated as shown in Figure 2F. To reveal the self-assembling process of the InTPP nanocrystals, the growth process of the nanowires with an aspect ratio of 81.3 was

7


Nano Letters 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

Figure 3. Properties of the InTPP nanocrystals synthesized at different CTAB concentrations. (A) UV−vis absorption spectra of the InTPP nanocrystals. (B) Powder XRD spectra of the InTPP nanocrystals. (C) The time-course data for photocatalytic H2 evolution under visible-light irradiation (1 mg of InTPP nanocrystals). (D) TEM images of the InTPP nanorods (aspect ratio of 21.0) with Pt nanoparticles after 30 min photodeposition.

monitored in situ using the SEM and UV-vis spectroscopy. It can be seen from the SEM images (Figure S4A) that large amount of random and irregular InTPP aggregates appeared within 3 min. The corresponding UV-vis spectroscopy showed that B band absorption and two Q bands of the nanostructures (Figure S4B) broadened and a new small shoulder peak at 451 nm appeared. As the self-assembly proceeded, irregular InTPP porphyrin aggregates disappeared and well-defined nanowires formed gradually. The absorption peak at 451 nm got sharper. These results indicated that formation of the InTPP porphyrin nanocrystals was a nucleation and growth process that occurs within μ-emulsion. 8


Page 8 of 18

Page 9 of 18 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

Nano Letters

To reveal the optical and structural properties of the InTPP porphyrin nanocrystals, UV-vis spectroscopy (Figure 3A) and powder XRD patterns (Figure 3B) of the nanocrystals were conducted. UV-vis absorption spectra were used to investigate the absorption spectra change of the assemblies in comparison with InTPP porphyrin monomers (dissolved in CHCl3). The UV-vis spectrum of the porphyrin chloroform solution displayed one Soret band at 425 nm and two Q-bands at 559 nm and 598 nm. In comparison, the Soret band of the porphyrin assemblies became red-shifted and much broader with the size increasing. A new shoulder peak between 429 nm and 451 nm appeared. In addition, the Q-band also shifted to red slightly. These characteristics suggest that these assemblies are J-aggregates,39 which results in the red-shift of absorption spectra for improving light-harvesting in the visible light absorption spectrum. Powder XRD patterns show that all the porphyrin assemblies have sharp and narrow diffraction peaks, indicating that they are very well crystallized and also have almost the same internal structure. Drawing inspiration from the arrangement of the chloroplasts in promoting efficient energy harvest and transfer, we investigated the InTPP nanocrystals for photocatalytic hydrogen generation under visible-light irradiation. The experiments were performed under visible excitation (λ > 400 nm) with ascorbic acid (AA) as the sacrificial agent and Pt nanoparticles as the co-catalyst. As shown in Figure 3C, all nanocrystals showed enhanced photocatalytic H2 evolution within 5 h of light irradiation. In comparison, the commercial porphyrin powders show negligible activity (1.1 µmol·mg-1·h-1). The highest H2-generation rate of 845.4 µmol·mg-1·h-1 is from the

9


Nano Letters 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

nanorods with the aspect ratio of 1.6, which is much higher than that of the commercial porphyrin powders under the same experimental conditions. These results also indicate that the H2 evolution performance of all the self-assembled nanocrystals is significantly improved compared with the commercial porphyrin powders. In addition, the performance is aspect ratio-dependent: nanocrystals with a smaller aspect ratio exhibit a higher H2 generation rate. We believe this is because the smaller aspect ratio nanorods have larger active surface area for such size-dependent photocatalytic reaction. Investigation of Pt deposition on the InTPP nanorods during photocatalytic reaction also supports this conclusion. Firstly, Pt nanoparticles as co-catalyst are crucial for charge separation during the photocatalytic process. We found that no H2 was detected in the absence of Pt nanoparticles. Secondly, high-resolution TEM (Figure 3D) was performed to characterize InTPP nanorods after the photocatalytic process (30 min). The Pt nanoparticles with the average size of ~2.2 nm were observed uniformly deposited on the InTPP nanorods (Figure S5), leading to the increase of the active sites, which may be responsible for such size-dependent and high photocatalytic property. To acquire a deep insight into the improved catalytic performance, a series of photo-electrochemical experiments were conducted to unveil the charge-separation efficiency. As shown in Figure 4A, photocurrent measurement results show that both Pt-decorated and pristine nanorods display much stronger photocurrent response than the commercial porphyrin powders, which is most likely

10


Page 10 of 18

Page 11 of 18 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

Nano Letters

Figure 4. Semiconductor character of the InTPP nanorods for H2 generation. (A) Photocurrents of the self-assembled InTPP nanocrystals and the commercial InTPP powder under visible light irradiation (λ > 400 nm). (B) Transient fluorescence lifetime of the self-assembled InTPP nanorods and the unassembled commercial InTPP powders. (C) Mott-Schottky plots for the InTPP nanorods (inset: energy-band diagram of the InTPP nanorods). (D) Tauc plot of the InTPP nanorods.

due to the close stacking between porphyrin molecules and long-range conjugated πelectron delocalization of the porphyrin assemblies. In addition, the Pt/InTPP nanorods get enhanced photocurrent compared to the pristine nanorods, suggesting that photoinduced electron-hole pairs are separated more efficiently in the presence of Pt nanoparticles. Therefore, the Pt-decorated InTPP nanorods have the best photocurrent performance for generating electron-hole pairs and suppressing their recombination, which is consistent with the observed photocatalytic efficiency. As shown in Figure

11


Nano Letters 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

4B, transient fluorescence lifetime of the self-assembled InTPP nanocrystals is 0.297 ns, which is much shorter than that of the unassembled commercial InTPP powders (0.689 ns). It is known that there exists intense fluorescence resonance energy transfer effect among porphyrin molecules in self-assembled nanostructures, which usually leads to a shorter fluorescence life time. The decreased decay time of the self-assembled InTPP nanocrystals indicate that more efficient transportation of photogenerated carriers in the self-assembled InTPP nanocrystals. To further elucidate the semiconductor character of the InTPP nanorods for H2 evolution upon visible-light excitation, Mott-Schottky (MS) analysis (Figure 4C) and Tauc plots (Figure 4D) were conducted. Mott-Schottky plots demonstrated that the InTPP nanorods were typical n-type semiconductor and the ﬂat band potential was found to be −0.35 V versus NHE. It was reported that the bottom of the conduction band (CB) in many n-type semiconductors is approximately equal to the flat band potential.40, 41 With bandgap energy (Eg) estimated by Tauc plots (Figure 4C, 1.92 eV), the valence bands of InTPP nanorods are accordingly obtained (1.57 V vs. NHE, shown in the inset of Figure 4C). This energy-band structure in InTPP nanorods makes them theoretically feasible for proton photoreduction (0 V vs. NHE). Deeper CB position (0.35 V) of the self-assembled InTPP supramolecular system provides thermodynamic driving force for H2 evolution. Upon visible light irradiation, photo generated electrons prefer to migrate from the nanorod assemblies to Pt nanoparticles through charge delocalization, leading to effective spatial charge separation and

12


Page 12 of 18

Page 13 of 18 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

Nano Letters

Figure 5. (A) Recycling test for the photocatalyzed H2 production by InTPP nanorods (aspect ratio of 21.0). (B) TEM image of the Pt/InTPP nanorods after reaction (60 h). (C) XRD results of the recycling catalysts before and after reaction. (D) UV-vis spectra of the recycling catalysts before and after reaction. Reaction conditions: 3 mg of InTPP nanorods loaded with 1 wt % of Pt cocatalyst; 0.2 M of ascorbic acid aqueous solution (50 mL) and 2 M NaOH was used to adjust the solution pH to 4.0; 300 W Xe lamp with a 400 nm cutoff filter; 5 % of AA sacrificial agent was added after per cycle.

enhanced photocatalytic efficiency. In general, the organic photocatalysts are limited by their photostability due to photobleaching or solvolysis. The self-assembled porphyrin nanocrystals have structural advantages with rigid aggregate framework, which would potentially protect them from erosion by reactive species and ensure better reusability. As shown in Figure 5A, the hydrogen production activity of the nanorods (aspect ratio of 21.0) was carried out up to 60 h under visible light irradiation to investigate the photo stability. In this case, 5% of AA sacrificial agent was added again per cycle. As shown in Figure 5A, 13


Nano Letters 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

the H2 production increased steadily with increasing irradiation time in every cycle. The slight rise in hydrogen evolution could be due to the addition of the sacrificial agent. Recycling experiments demonstrated that no noticeable activity decreasing occurs during the 12 catalytic runs. Furthermore, the TEM images (Figure 5B) and the powder XRD results (Figure 5C) both confirm that the structural integrity and crystallinity of nanorods are well retained. Correspondingly, the UV-vis spectra (Figure 5D) of the nanorods are also kept the same, indicating that the self-assembled structure within the nanorods remains no changes after the reaction. It is interesting to note that the hydrogen production efficiency of the shorter nanorods with aspect ratio of 1.6 decreases starting from the fifth cycle (Figure S6). This is probably due to the lower light tolerance of smaller nanocrystals. In summary, we demonstrated the synthesis of a new class of narrow-band semiconductor light-harvesting InTPP nanocrystals through the μ-emulsion assisted self-assembly process. Morphology and dimension such as aspect ratio of the nanocrystals can be systematically modulated by the surfactant concentrations. In comparison with the original porphyrin monomers, the ordered molecular packing structure enables effective molecular coupling and renders the resultant porphyrin nanocrystals with enhanced optical absorption and photocatalytic hydrogen generation properties under visible light. The photocurrent and fluorescence lifetime results further demonstrated the efficient separation and low recombination of photo-induced carriers in InTPP self-assembled nanocrystals for the boosted efficiency of the H2 generation. Our findings not only highlight the great potential and advantages of the self-assembled

14


Page 14 of 18

Page 15 of 18 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

Nano Letters

supermolecular architectures, but also present a new platform for the development of high-efficiency photocatalysts for utilizing solar energy.

ASSOCIATED CONTENT Supporting Information. Preparation of self-assembled nanomaterials and their characterizations including TEM, SEM, size analysis, and UV-vis (PDF).

AUTHOR INFORMATION Corresponding Author *F.B. ([email protected]), Tel: 86-15039024866, Fax: 86-0371-23883868 *H.F. ([email protected]), Tel: (505) 272-7128, Fax: (505) 272-7336

Author Contributions F.B., H.F. conceived the idea. Y.L., L.W., H.Feng, X.R., J.J. and F.B. performed the experiments. All authors commented on the manuscript and contributed to the writing of the manuscript.

Notes The authors declare no competing financial interest.

ACKNOWLEDGMENT F.B. acknowledges the support from the National Natural Science Foundation of China (21771055, U1604139, 21601049, 21171049, 21422102), Plan for Scientific 15


Nano Letters 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

Innovation Talent of Henan Province (No. 174200510019), and Program for Changjiang Scholars and Innovative Research Team in University (No. PCS IRT_15R18). This paper describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the U.S. Department of Energy or the United States Government. Research was carried out, in part, at the Center of Integrated Nanotechnology (CINT), a US Department of Energy, Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525. REFERENCES (1) Amunts, A.; Toporik, H.; Borovikova, A.; Nelson, N. J. Biol. Chem. 2010, 285, 3478-3486. (2) Bard, A. J.; Fox, M. A. Acc. Chem. Res. 1995, 28, 141-145. (3) Kundu, S.; Patra, A. Chem. Rev. 2017, 117, 712-757. (4) Zhou, H.; Li, X.; Fan, T.; Osterloh, F. E.; Ding, J.; Sabio, E. M.; Zhang, D.; Guo, Q. Adv. Mater. 2010, 22, 951-956. (5) Zhao, L.; Zou, H.; Zhang, H.; Sun, H.; Wang, T.; Pan, T.; Li, X.; Bai, Y.; Qiao, S.; Luo, Q.; Xu, J.; Hou, C.; Liu, J. ACS Nano 2017, 11, 938-945. (6) Dubey, R. K.; Inan, D.; Sengupta, S.; Sudhölter, E. J. R.; Grozema, F. C.; Jager, W. F. Chem. Sci. 2016, 7, 3517-3532. (7) Wasielewski, M. R. Acc. Chem. Res. 2009, 42, 1910-1921. (8) Wu, Z.; Yan, Y.; Huang, J. Langmuir 2014, 30, 14375-14384. (9) Frischmann, P. D.; Mahata, K.; Würthner, F. Chem. Soc. Rev. 2013, 42, 1847-1870. (10) Sun, M.-J.; Liu, Y.; Yan, Y.; Li, R.; Shi, Q.; Zhao, Y. S.; Zhong, Y.-W.; Yao, J. J. Am. Chem. Soc. 2018, 140, 4269-4278. (11) Zhang, L.; Wang, X.; Wang, T.; Liu, M. Small 2015, 11, 1025-1038. (12) Weingarten, A. S.; Kazantsev, R. V.; Palmer, L. C.; McClendon, M.; Koltonow, A. R.; Samuel, A. P. S.; Kiebala, D. J.; Wasielewski, M. R.; Stupp, S. I. Nat. Chem. 2014, 6, 964. (13) Liu, D.; Wang, J.; Bai, X.; Zong, R.; Zhu, Y. Adv. Mater. 2016, 28, 7284-7290. (14) Zang, L.; Che, Y.; Moore, J. S. Acc. Chem. Res. 2008, 41, 1596-1608. (15) Weingarten, A. S.; Kazantsev, R. V.; Palmer, L. C.; Fairfield, D. J.; Koltonow, A. R.; Stupp, S. I. J. Am. Chem. Soc. 2015, 137, 15241-15246. (16) Elemans, J. A. A. W.; van Hameren, R.; Nolte, R. J. M.; Rowan, A. E. Adv. Mater. 2006, 18, 12511266. (17) Kim, J. H.; Nam, D. H.; Lee, Y. W.; Nam, Y. S.; Park, C. B. Small 2014, 10, 1272-1277. (18) Jiang, J.; Meng, Y.; Zhang, L.; Liu, M. J. Am. Chem. Soc. 2016, 138, 15629-15635. (19) Son, H.-J.; Jin, S.; Patwardhan, S.; Wezenberg, S. J.; Jeong, N. C.; So, M.; Wilmer, C. E.; Sarjeant, A. A.; Schatz, G. C.; Snurr, R. Q.; Farha, O. K.; Wiederrecht, G. P.; Hupp, J. T. J. Am. Chem. Soc. 2013, 135, 862-869. (20) Qiu, Y.; Chen, P.; Liu, M. J. Am. Chem. Soc. 2010, 132, 9644-9652. (21) Tian, Y.; Martin, K. E.; Shelnutt, J. Y. T.; Evans, L.; Busani, T.; Miller, J. E.; Medforth, C. J.;

16


Page 16 of 18

Page 17 of 18 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

Nano Letters

Shelnutt, J. A. Chem. Commun. 2011, 47, 6069-6071. (22) Guo, P.; Chen, P.; Ma, W.; Liu, M. J. Mater. Chem. 2012, 22, 20243-20249. (23) Wang, Z. C.; Medforth, C. J.; Shelnutt, J. A. J. Am. Chem. Soc. 2004, 126, 15954-15955. (24) Medforth, C. J.; Wang, Z.; Martin, K. E.; Song, Y.; Jacobsen, J. L.; Shelnutt, J. A. Chem. Commun. 2009, 7261-7277. (25) Bai, F.; Sun, Z.; Wu, H.; Haddad, R. E.; Coker, E. N.; Huang, J. Y.; Rodriguez, M. A.; Fan, H. Nano Lett. 2011, 11, 5196-5200. (26) Bai, F.; Sun, Z.; Wu, H.; Haddad, R. E.; Xiao, X.; Fan, H. Nano Lett. 2011, 11, 3759-3762. (27) Wang, D.; Niu, L.; Qiao, Z.-Y.; Cheng, D.-B.; Wang, J.; Zhong, Y.; Bai, F.; Wang, H.; Fan, H. ACS Nano 2018, 12, 3796-3803. (28) Wang, J.; Zhong, Y.; Wang, X.; Yang, W.; Bai, F.; Zhang, B.; Alarid, L.; Bian, K.; Fan, H. Nano Lett. 2017, 17, 6916-6921. (29) Bai, F.; Li, B.; Bian, K.; Haddad, R.; Wu, H.; Wang, Z.; Fan, H. Adv. Mater. 2016, 28, 1989-1993. (30) Zhang, W.; Lai, W.; Cao, R. Chem. Rev. 2017, 117, 3717-3797. (31) Kesters, J.; Verstappen, P.; Kelchtermans, M.; Lutsen, L.; Vanderzande, D.; Maes, W. Adv. Energy Mater. 2015, 5, 1500218. (32) Paolesse, R.; Nardis, S.; Monti, D.; Stefanelli, M.; Di Natale, C. Chem. Rev. 2017, 117, 2517-2583. (33) Zhang, N.; Wang, L.; Wang, H.; Cao, R.; Wang, J.; Bai, F.; Fan, H. Nano Lett. 2018, 18, 560-566. (34) Zhong, Y.; Wang, J.; Zhang, R.; Wei, W.; Wang, H.; Lü, X.; Bai, F.; Wu, H.; Haddad, R.; Fan, H. Nano Lett. 2014, 14, 7175-7179. (35) Wang, J.; Zhong, Y.; Wang, L.; Zhang, N.; Cao, R.; Bian, K.; Alarid, L.; Haddad, R. E.; Bai, F.; Fan, H. Nano Lett. 2016, 16, 6523-6528. (36) Zhang, C.; Chen, P.; Dong, H.; Zhen, Y.; Liu, M.; Hu, W. Adv. Mater. 2015, 27, 5379-5387. (37) Bai, F.; Wang, D.; Huo, Z.; Chen, W.; Liu, L.; Liang, X.; Chen, C.; Wang, X.; Peng, Q.; Li, Y. Angew. Chem. Int. Ed. 2007, 46, 6650-6653. (38) Zhong, Y.; Wang, Z.; Zhang, R.; Bai, F.; Wu, H.; Haddad, R.; Fan, H. ACS Nano 2014, 8, 827-833. (39) McRae, E. G.; Kasha, M. J. Chem. Phys. 1958, 28, 721-722. (40) Xu, H.-Q.; Hu, J.; Wang, D.; Li, Z.; Zhang, Q.; Luo, Y.; Yu, S.-H.; Jiang, H.-L. J. Am. Chem. Soc. 2015, 137, 13440-13443. (41) Leng, F.; Liu, H.; Ding, M.; Lin, Q.-P.; Jiang, H.-L. ACS Catalysis 2018, 8, 4583-4590.

TOC Figure

17


Nano Letters 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 18


Page 18 of 18

Microemulsion-Assisted Self-Assembly and Synthesis of Size

Recommend Documents