Direct Synthesis of Crystalline Graphdiyne Analogue Based on

2 days ago - Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, CAS Key ...
0 downloads 0 Views 873KB Size
Download PDF
Subscriber access provided by University of Winnipeg Library

Communication

Direct Synthesis of Crystalline Graphdiyne Analogue Based on Supramolecular Interactions Weixiang Zhou, Han Shen, Chenyu Wu, Zeyi Tu, Feng He, Yanan Gu, Yurui Xue, Yingjie Zhao, Yuanping Yi, Yongjun Li, and Yuliang Li J. Am. Chem. Soc., Just Accepted Manuscript • DOI: 10.1021/jacs.8b09945 • Publication Date (Web): 20 Dec 2018 Downloaded from http://pubs.acs.org on December 20, 2018

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 5 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

Journal of the American Chemical Society

Direct Synthesis of Crystalline Graphdiyne Analogue Based on Supramolecular Interactions †‡ †‡ † †‡ † Weixiang Zhou,†,‡ Han Shen, , Chenyu Wu,§ Zeyi Tu, , Feng He, Yanan Gu, , Yurui Xue, Yingjie † ‡ † ‡ † ‡ Zhao,§ Yuanping Yi, , Yongjun Li*, , and Yuliang Li , †

Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China ‡

University of Chinese Academy of Sciences, Beijing 100049, P. R. China

§

College of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China

Supporting Information Placeholder ABSTRACT: The synthesis of graphdiyne with an ordered internal structure is highly attractive for its various scientific and application investigations. We reported herein a rational method to fabricate a graphdiyne analogue with the help of supramolecular chemistry. The introduction of π-π/CH-π interactions controlled the conformations of the precursors and afforded multilayer graphdiyne analogue Ben-GDY through the wet chemical method. The in-plane periodicity of the multilayer Ben-GDY was corroborated by transmission electron microscope (TEM) and selected area electron diffraction (SAED), which showed a pattern well matched with ABC-style stacking.

Two-dimensional (2D) carbon materials have captured great attentions due to their potential technological applications in nanoelectronics, energy storage, batteries1,2. The prerequisite for the success of 2D polymerizations is the precise control of monomer assembly before or in the process of covalent bond generation, if not, aperiodic, crosslinked networks are preferred. Shapepersistent monomers and directional interactions, that is, an interface or layered crystal, were used to control specific bonding geometries for templating the formation of the target 2D structure. The sp- and sp2 -hybridized graphdiyne (GDY)2-5 exhibits highly conjugated π system, conformably distributed pores, and controllable electronic properties6, which perform in various applications comparable to conventional sp2 hybridized carbon systems. The reliable fabrication of GDY extend its study from theoretical predictions into practical investigations, where it has exhibited many applications such as catalyst7-9, rechargeable batteries10-12, solar cells13 electronic devices14, detectors15, biomedicine and therapy16, and water purification17. The synthesis of GDY was first achieved through a Glaser coupling reaction on copper foil4, in which the copper foil functioned as the reservoir of coupling catalysts and the planar template for the controlled conformal growth of 2D GDY sheets. Following this ground-breaking work, GDY has been fabricated in the morphologies of nanowires18, nanotube arrays19, nanowalls20, nanosheets 10,21-23 and three-dimensional (3D) foams24 etc. Though crystalline graphdiyne nanowalls9,20, nanosheets22 have been successfully constructed and the crystal structure was determined by high-resolution TEM, it is still an extremely challenge

to fabricate high-quality graphdiyne films due to the fact that 1) some types of side reactions like trimerization, hydroalkynylation and oxidation would occur for the reactive monomer hexaethynylbenzene25, 2) irregular cross linking between two ethynyl groups due to the free rotation of the single bond, both bringing to the random polymeric systems. To overcome these problems, there are two aspects can be considered. First, the utilization of an appropriate flat substrate interacting with the precursors might enhance the ability to generate the desired 2D networks. Second, introduction of supramolecular interactions to control the orientation of the monomers and the growing oligmers, thus avoiding defects and providing high crystallinity in the target networks, which is the key feature of the strategy that would be investigated here. Herein we reported the design and synthesis of a highly crystalline graphdiyne analogue, benzene substituted graphdiyne (BenGDY). Ben-GDY is an extended π-conjugated carbon network with six 1,3,5-triphenylbenzene rings connected with butadiyne linkages as the repeating hexagonal unit. The optimized framework of Ben-GDY is plotted in Figure 1(b). The length of the acetylenic bond (C2-C3) in the butadiyne linkage is around 1.214 Å. Because of the stabilization effect of the triple bonds, both of the lengths of the bonds between C1 and C2 (1.393 Å) and that of C3-C3(1.332 Å) are shorter than the C1-C1 bond. The Ben-GDY framework is a flat plane without any buckling. The sheet of BenGDY can be described by the plane group P1 with a lattice constant of a=16.145Å, b=16.147Å, γ=120.134°. The phenyl rings connected with the triethynylphenyl frame work with dihedral angles of 40.0~40.2°. The vicinity of alkynes was attached with benzene rings to provide the increased stability of the monomer through the bulkyprotection of alkynes. The π-π/CH-π interactions between the nearby benzene rings in the oligmers can force the alkyne skeleton into near flat surface, as evidenced by the fact that the model dimerwith parallel conformation showed ~4.5 kcal mol-1 lower energy than the vertical one (Figure 2b), which could gather a large stabilization energy in the target network. These π-π/CH-π interactions were also evidenced in the optimized structure as the short C-H… C contacts of 2.26~2.49 Å between the attached benzene C-H and the butadiyne carbon, and the short C-H…C contacts of 2.79~2.82 Å between attached benzene rings (Figure 1b). At the same condi

ACS Paragon Plus Environment

Journal of the American Chemical Society 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 1. Supramolecular approach for ordered 2D graphdiyne. a) 1,3,5-triethynylbenzene without directional interactions formed 3D porous film11. b) The introduction of π-π/CH-π interactions for controlling the flat bonding geometries, C1, C2, C3, C4 are denoted (black red), the torsion angles of the attached benzene rings (purple), the bond lengths (blue), C-H…C short contacts (red) and the cavity (d =5.1 Å) surrounded by attached benzenes are shown, the unit cell of Ben-GDY denoted by the black line. tions, the hexethynyl dimmer showed only ~0.1 kcal mol-1 rotation barriers (Figure 2b), which decreased the probability to form crystalline films. The modeling of the key step in Bohlmann’s coupling mechanism26 (Figure S1) indicated that the introduction of nearby benzene rings would increase the homocoupling reaction barrier due to repulsion between benzene rings, therefore higher reaction temperature would be expected. The single-crystal X-ray diffraction (XRD) analysis of the monomer 3 (Figure 2c) and 6 (Figure 2d) revealed some key π-π/CH-π interactions needed for the assembly of monomers to the intermediates or the bottom layer grown previously. These supramolecular interactions ensured the lateral growth of the layers on the copper surface and prevented the cross-linking across the layers. The synthesis of monomer 3 was shown in supporting information. Ben-GDY was prepared via the Glaser-Hay coupling reaction of 3 in pyridine with copper foil as the substrate and catalyst at higher temperature (110 ºC) as expected. XPS (Figure S2) shows that the Ben-GDY film consists of elemental carbon. Deconvolution and curve fitting of the C 1 s core level spectra displays the major fractions of C-C(sp2, 284.7 eV ), C-C(sp, 285.4 eV), C-O (286.5 eV), and C=O (288.8 eV) (Figure 3a). The existence of C=O and C-O groups is ascribed to the oxygenization of the terminal alkyne on the edge of the 2D molecular framework. The appearance of the Raman signal at 2192 cm−1 (the C≡C stretching) in the Ben-GDY films (Figure 3b) is a strong proof for the generation of conjugated butadiyne bridges from the coupling reaction of the terminal alkyne (which shows a C≡C vibration at 2115 cm−1; Figure S3). G-band at 1593 cm-1 indicates that the Ben-GDY films contain abundant aromatic rings, and a D-band at 1374 cm-1 is assigned to the vibration of the bonds connecting two carbon triple bonds and the stretching of the C-C bonds connect

Figure 2. Supramolecular interactions for controlling the molecular geometry and pre-organization. a) The molecular structures of the model dimmer di-triethynyl-benzene (DiTEB) and dihexaethynylbenzene (DiHEB); b) Torsion barriers of DiTEB and DiHEB along the torsion angle as indicated in a). Crystal structures of the monomer 3 (c), and 6 (d), in which the CH-π interactions critical for stacking of layers were indicated: a: 3.068 Å, b: 2.844 Å, c: 2.884 Å, d: 2.861Å; CH-π interactions critical for assembling alkyne units towards following coupling reactions were emphasized: e: 2.798 Å, f: 2.810 Å, g: 2.772 Å. ing triply-coordinated carbon atoms and its doubly-coordinated carbon neighbors, also the stretching of C-C bonds connecting doubly coordinated phenyl rings carbon atoms27. The observed signals agree well with the simulated Raman spectra calculated at HSE06/def2-SVP level (also combined with DFT-D3 dispersion correction) of theory, which supports the proposed assignments (Figure S9). C K-edge NEXAFS spectrum of Ben-GDY (Figure S11) showed the π* orbitals of the ethynyl group, which further confirmed the formation of butadiyne bridge28. The ultraviolet-visible (UV−vis) absorption analysis was employed to investigate the optical properties of Ben-GDY film. An obvious bathochromic shift was observed in the UV−vis spectra of the Ben-GDY film as compared with that of the monomer 3, which is ascribed to the enhanced electron delocalization through the highly π-conjugation. The optical bandgap (Ebg) estimated from the absorption onset is 2.47 eV (Figure 3c). The energy level of valence band (i.e., Evb) of Ben-GDY was measured by ultraviolet photoelectron spectroscopy (UPS). Subtracting the UPS width (Figure S4) from excitation energy (HeI, 21.22 eV gave the Evb of 6.61 eV. Furthermore, the conduction band energy Ecb (4.14 eV) was obtained from Evb – Ebg. The electronic band gap of BenGDY agrees with the that of 1,3,5-graphdiyne reported by Barth et al.29 The current–voltage (I–V) curve was also measured at a bias voltage from –1 to 1 V (Figure 3d). The conductivity of BenGDY film is determined to be 6.77×10-3 S m-1. The electronic band structure and corresponding PDOS of BenGDY are calculated under HSE06 functional in the Brillouin zone and given in Figure 3e. Both valence-band maximum (VBM) and conduction-band minimum (CBM) are found to be located at the first Brillouin zone Γ point. The calculated band gap energy

ACS Paragon Plus Environment

Page 2 of 5

Page 3 of 5 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

Journal of the American Chemical Society

Figure 3. Spectral characterization and electronic band structure of Ben-GDY. a) XPS spectra of Ben-GDY. b) Experimental and simulated Raman spectra of Ben-GDY. c) UV-vis spectra of BenGDY film exfoliated from the copper foil, the bandgap was given by the onset of the absorption. d) Conductivity measurement of Ben-GDY film on the copper substrate. e) Calculated electronic band structure and corresponding partial density of states (PDOS) of Ben-GDY. The black, red, blue and cyan lines present the total density of states, PDOS of C≡C (sp C, C2,C3), C=C (sp2 C, C1), C=C (sp2 C, C4), respectively. The first Brillouin zone high symmetry points are labeled as follows: Γ (0, 0, 0), B (1/2, 0, 0), F (0, 1/2, 0); f) Wave function of highest occupied crystal orbital (HOCO) and lowest unoccupied crystal orbital (LUCO) at Γ point in unit cell of Ben-GDY. of Ben-GDY is 2.66 eV, which is consistent well with the measured optical band gap (2.47 eV). HOCO and LUCO at Γ point in unit cell of Ben-GDY are plotted in Figure 3f (Figure S8). Both CBM and VBM are two-fold degenerated at Γ point. The HOCO is mainly localized at the π orbital of hexagonal benzene rings and C≡C bonds. However, the LUCO is located at the σ* bond connecting the attached benzene rings and that connecting the C≡C chains with the framework benzene. Ben-GDY is semiconducting due to these highly localized π HO and σ* LU orbitals, which are different from the delocalized π and π* orbitals of metallic graphene sheet. Optical microscopy of the Ben-GDY film transferred to a quartz substrate revealed sheet morphology (inset of Figure 4a). Atomic force microscopy (AFM) showed the nanoscale morphology of Ben-GDY film (Figure 4a). The film was revealed to be a 30 nm thick flat sheet. SEM images again showed the smooth surface of the Ben-GDY film (Figure 4b), and EDS point analysis indicated the appearance of carbon, trace oxygen and without copper (Figure S5). Compared with the reported 3D porous film11 and nanofibers film30 grown from triethynylbenzene on copper foil in pyridine, our supramolecular strategy successfully controlled the conformation of the intermediate oligmers and ensured

Figure 4. a) AFM images of exfoliated sheets, inset, height analysis along the green lines (across the slit generated by stresscracking) shows a uniform thickness of ~30 nm; Digital photograph of the Ben-GDY film transferred to a quartz substrate, a hole generated by the solvent evaporation induced stress-cracking. b) The SEM images of Ben-GDY film. c) TEM image of BenGDY film. d) HRTEM of Ben-GDY. e) Scanning TEM image, f) elemental mapping of the C in the Ben-GDY nanosheets, g) an overlay of these two images. h) SAED of Ben-GDY film. Simulated ABC stacking model of Ben-GDY: i) top view, j) side view. the lateral growth of the layers on the copper surface (the detailed growth mechanism was shown in Figure S12). The powder XRD pattern (Figure S13) indicates the crystallinity of Ben-GDY film. The diffraction peak at 15.239ºcorresponds to the 0.58 nm interlayer spacing. The strong diffraction peak at 18.920ºrelates to the diffraction spacing of 0.47 nm. The internal structure of the Ben-GDY was investigated by SAED performed in a TEM. Figure 4c gives a typical lowmagnification TEM image of the Ben-GDY film. Elemental mapping of the selected region in Figure 4e showed the uniform carbon atoms distribution (Figure 4e-g). The hexagonal pattern 2D periodicity revealed by SAED (Figure 4h) confirms the high crystallinity of the Ben-GDY (Figure 1b). The experimental diffraction pattern almost exactly matched that expected for the proposed ABC stacking model (Figure 4i,j) (Figure S14-16). Hence, the trigonal crystal structure with ABC stacking (space group R32) was confirmed for the graphdiyne synthesized in this work. HRTEM of the synthesized Ben-GDY film (Figure 4d) revealed the 0.47 nm interval lattice fringes, which is related to (3 0 0) spacing of the primitive unit cell.

ACS Paragon Plus Environment

Journal of the American Chemical Society 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

In summary, we have synthesized a carbon-rich 2D graphdiyne analogue with the help of supramolecular chemistry. The introduction of π-π/CH-π interactions controlled the conformations of the precursors and afforded crystalline multilayer graphdiyne analogue. TEM and SAED corroborated the in-plane periodicity of the multilayer Ben-GDY, and the SAED pattern revealed the ABC- type stacking. This kind of synthetic 2D materials with an ordered internal structure are greatly beneficial for their various scientific and application investigations.

ASSOCIATED CONTENT

Supporting Information The synthesis procedures and characterization data. The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/jacs.XXX.

AUTHOR INFORMATION Corresponding Author *[email protected]

Notes The authors declare no competing financial interests.

ACKNOWLEDGMENT This work was supported by the National Nature Science Foundation of China (21672222, 21790050, 21790051), NSFC-DFG joint fund (21661132006), the National key research and development project of China (2016YFA0200104), the key program of the Chinese Academy of Science (QYZDY-SSW-SLH015), and the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA09020302).

REFERENCES (1) Diederich, F.; Kivala, M. All-Carbon Scaffolds by Rational Design, Adv. Mater. 2010, 22, 803. (2) Li, Y. J.; Xu, L.; Liu, H. B.; Li, Y. L. Graphdiyne and graphyne: from theoretical predictions to practical construction, Chem. Soc. Rev. 2014, 43, 2572. (3) Jia, Z.; Li, Y.; Zuo, Z.; Liu, H.; Huang, C.; Li, Y. Synthesis and Properties of 2D Carbon-Graphdiyne, Acc. Chem. Res. 2017, 50, 2470. (4) Li, G. X.; Li, Y. L.; Liu, H. B.; Guo, Y. B.; Li, Y. J.; Zhu, D. B. Architecture of graphdiyne nanoscale films, Chem. Commun. 2010, 46, 3256. (5) Huang, C.; Li, Y.; Wang, N.; Xue, Y.; Zuo, Z.; Liu, H.; Li, Y. Progress in Research into 2D Graphdiyne-Based Materials, Chem. Rev. 2018, 118, 7744. (6) Li, Z. H.; Smeu, M.; Rives, A.; Maraval, V.; Chauvin, R.; Ratner, M. A.; Borguet, E. Towards graphyne molecular electronics, Nat. Commun. 2015, 6, 6321. (7) Qi, H.; Yu, P.; Wang, Y.; Han, G.; Liu, H.; Yi, Y.; Li, Y.; Mao, L. Graphdiyne Oxides as Excellent Substrate for Electroless Deposition of Pd Clusters with High Catalytic Activity, J. Am. Chem. Soc. 2015, 137, 5260. (8) Xue, Y.; Huang, B.; Yi, Y.; Guo, Y.; Zuo, Z.; Li, Y.; Jia, Z.; Liu, H.; Li, Y. Anchoring zero valence single atoms of nickel and iron on graphdiyne for hydrogen evolution, Nat. Commun. 2018, 9, 1460. (9) Gao, X.; Li, J.; Du, R.; Zhou, J.; Huang, M.-Y.; Liu, R.; Li, J.; Xie, Z.; Wu, L.-Z.; Liu, Z.; Zhang, J. Direct Synthesis of Graphdiyne Nanowalls on Arbitrary Substrates and Its Application for Photoelectrochemical Water Splitting Cell, Adv. Mater. 2017, 29, 1605308. (10) Shang, H.; Zuo, Z.; Li, L.; Wang, F.; Liu, H.; Li, Y.; Li, Y. Ultrathin Graphdiyne Nanosheets Grown InSitu on Copper Nanowires and Their Performance as Lithium-Ion Battery Anodes, Angew. Chem. Int. Ed. 2018, 57, 774. (11) Wang, N.; He, J.; Tu, Z.; Yang, Z.; Zhao, F.; Li, X.; Huang, C.; Wang, K.; Jiu, T.; Yi, Y.; Li, Y. Synthesis of Chlorine-Substituted

Page 4 of 5

Graphdiyne and Applications for Lithium-Ion Storage, Angew. Chem. Int. Ed. 2017, 56, 10740. (12) He, J.; Wang, N.; Cui, Z.; Du, H.; Fu, L.; Huang, C.; Yang, Z.; Shen, X.; Yi, Y.; Tu, Z.; Li, Y. Hydrogen substituted graphdiyne as carbon-rich flexible electrode for lithium and sodium ion batteries, Nat. Commun. 2017, 8, 1172. (13) Xiao, J. Y.; Shi, J. J.; Liu, H. B.; Xu, Y. Z.; Lv, S. T.; Luo, Y. H.; Li, D. M.; Meng, Q. B.; Li, Y. L. Efficient CH3NH3PbI3 Perovskite Solar Cells Based on Graphdiyne (GD)-Modified P3HT Hole-Transporting Material, Adv. Energy Mater. 2015, 5, 1401943. (14) Lu, C.; Yang, Y.; Wang, J.; Fu, R.; Zhao, X.; Zhao, L.; Ming, Y.; Hu, Y.; Lin, H.; Tao, X.; Li, Y.; Chen, W. High-performance graphdiynebased electrochemical actuators, Nat. Commun. 2018, 9, 752. (15) Yan, H.; Guo, S.; Wu, F.; Yu, P.; Liu, H.; Li, Y.; Mao, L. Carbon Atom Hybridization Matters: Ultrafast Humidity Response of Graphdiyne Oxides, Angew. Chem. Int. Ed. 2018, 57, 3922. (16) Parvin, N.; Jin, Q.; Wei, Y.; Yu, R.; Zheng, B.; Huang, L.; Zhang, Y.; Wang, L.; Zhang, H.; Gao, M.; Zhao, H.; Hu, W.; Li, Y.; Wang, D. FewLayer Graphdiyne Nanosheets Applied for Multiplexed Real-Time DNA Detection, Adv. Mater. 2017, 29, 1606755. (17) Lin, S. C.; Buehler, M. J. Mechanics and molecular filtration performance of graphyne nanoweb membranes for selective water purification, Nanoscale 2013, 5, 11801. (18) Qian, X. M.; Ning, Z. Y.; Li, Y. L.; Liu, H. B.; Ouyang, C. B.; Chen, Q.; Li, Y. J. Construction of graphdiyne nanowires with high-conductivity and mobility, Dalton Trans. 2012, 41, 730. (19) Li, G. X.; Li, Y. L.; Qian, X. M.; Liu, H. B.; Lin, H. W.; Chen, N.; Li, Y. J. Construction of Tubular Molecule Aggregations of Graphdiyne for Highly Efficient Field Emission, J. Phys. Chem. C 2011, 115, 2611. (20) Zhou, J. Y.; Gao, X.; Liu, R.; Xie, Z. Q.; Yang, J.; Zhang, S. Q.; Zhang, G. M.; Liu, H. B.; Li, Y. L.; Zhang, J.; Liu, Z. F. Synthesis of Graphdiyne Nanowalls Using Acetylenic Coupling Reaction, J. Am. Chem. Soc. 2015, 137, 7596. (21) Liu, R.; Gao, X.; Zhou, J.; Xu, H.; Li, Z.; Zhang, S.; Xie, Z.; Zhang, J.; Liu, Z. Chemical Vapor Deposition Growth of Linked Carbon Monolayers with Acetylenic Scaffoldings on Silver Foil, Adv. Mater. 2017, 29, 1604665. (22) Matsuoka, R.; Sakamoto, R.; Hoshiko, K.; Sasaki, S.; Masunaga, H.; Nagashio, K.; Nishihara, H. Crystalline Graphdiyne Nanosheets Produced at a Gas/Liquid or Liquid/Liquid Interface, J. Am. Chem. Soc. 2017, 139, 3145. (23) Li, C.; Lu, X.; Han, Y.; Tang, S.; Ding, Y.; Liu, R.; Bao, H.; Li, Y.; Luo, J.; Lu, T. Direct imaging and determination of the crystal structure of six-layered graphdiyne, Nano Res. 2018, 11, 1714. (24) Gao, X.; Zhou, J.; Du, R.; Xie, Z.; Deng, S.; Liu, R.; Liu, Z.; Zhang, J. Robust Superhydrophobic Foam: A Graphdiyne-Based Hierarchical Architecture for Oil/Water Separation, Adv. Mater. 2016, 28, 168. (25) Wang, J. Y.; Zhang, S. Q.; Zhou, J. Y.; Liu, R.; Du, R.; Xu, H.; Liu, Z. F.; Zhang, J.; Liu, Z. R. Identifying sp-sp(2) carbon materials by Raman and infrared spectroscopies, Phys. Chem. Chem. Phys. 2014, 16, 11303. (26) Bohlmann, F.; Schonowsky, H.; Grau, G.; Inhoffen, E. Polyacetylenverbindungen. 52. Uber den mechanismus der oxydativen dimerisierung von acetylenverbindungen, Chem. Ber. Recl. 1964, 97, 794. (27) Zhang, S.; Wang, J.; Li, Z.; Zhao, R.; Tong, L.; Liu, Z.; Zhang, J.; Liu, Z. Raman Spectra and Corresponding Strain Effects in Graphyne and Graphdiyne, J. Phys. Chem. C 2016, 120, 10605. (28) Zhong, J.; Wang, J.; Zhou, J. G.; Mao, B. H.; Liu, C. H.; Liu, H. B.; Li, Y. L.; Sham, T. K.; Sun, X. H.; Wang, S. D. Electronic Structure of Graphdiyne Probed by X-ray Absorption Spectroscopy and Scanning Transmission X-ray Microscopy, J. Phys. Chem. C 2013, 117, 5931. (29) Klappenberger, F.; Zhang, Y. Q.; Bjork, J.; Klyatskaya, S.; Ruben, M.; Barth, J. V. On-Surface Synthesis of Carbon-Based Scaffolds and Nanomaterials Using Terminal Alkynes, Acc. Chem. Res. 2015, 48, 2140. (30) Zhang, T.; Hou, Y.; Dzhagan, V.; Liao, Z.; Chai, G.; Loeffler, M.; Olianas, D.; Milani, A.; Xu, S.; Tommasini, M.; Zahn, D. R. T.; Zheng, Z.; Zschech, E.; Jordan, R.; Feng, X. Nat. Commun. 2018, 9, 1140.

ACS Paragon Plus Environment

Page 5 of 5 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

Journal of the American Chemical Society SYNOPSIS TOC (Word Style “SN_Synopsis_TOC”).

ACS Paragon Plus Environment