Wang Yong, Sofer Zdeněk, Luxa Jan, Chia Xinyi, Pumera Martin
Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Science, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore, Singapore.
Department of Inorganic Chemistry, University of Chemistry and Technology Prague, Technicka 5, 166 28, Prague 6, Czech Republic.
Chemistry. 2017 Aug 1;23(43):10430-10437. doi: 10.1002/chem.201701843. Epub 2017 Jul 11.
In comparison to the extensive research and great success attained by Group 6 transition metal dichalcogenides (TMDs) as hydrogen evolution reaction (HER) electrocatalysts, there is limited research focused on metallic Group 5 TMDs for use as electrocatalysts for hydrogen evolution. Density functional theory calculations have pointed out that Group 5 TMDs are highly favorable for HER, especially vanadium disulfide. In this work, nanocomposites of graphene and Group 5 TMDs were synthesized by thermal exfoliation of graphene oxide/TMD precursors in an H S atmosphere or in a H atmosphere as a control. Graphene oxide was prepared by the Hummers method while vanadium tetrachloride, niobium pentachloride, and tantalum pentachloride were utilized as TMD precursors. Then the potential of these nanocomposites as electrocatalysts towards HER was explored. Although these nanocomposites do not have comparable HER performance to Group 6 TMDs, they exhibit higher electrocatalytic activity in comparison with thermally reduced graphene oxide (TRGO) in the absence of TMD modification. In addition, the capacitive performance of these materials was also investigated in consideration of the high capacitance of graphene. It was indicated that the presence of TMDs on graphene actually suppress the capacitance performance of graphene itself.
与第6族过渡金属二硫属化物（TMDs）作为析氢反应（HER）电催化剂所取得的广泛研究和巨大成功相比，针对用作析氢电催化剂的第5族金属TMDs的研究有限。密度泛函理论计算指出，第5族TMDs对析氢非常有利，尤其是二硫化钒。在这项工作中，通过在H₂S气氛中或作为对照在H₂气氛中对氧化石墨烯/TMD前驱体进行热剥离，合成了石墨烯与第5族TMDs的纳米复合材料。氧化石墨烯通过Hummers法制备，同时使用四氯化钒、五氯化铌和五氯化钽作为TMD前驱体。然后探索了这些纳米复合材料作为析氢电催化剂的潜力。尽管这些纳米复合材料的析氢性能无法与第6族TMDs相媲美，但与未进行TMD改性的热还原氧化石墨烯（TRGO）相比，它们表现出更高的电催化活性。此外，考虑到石墨烯的高电容，还研究了这些材料的电容性能。结果表明，石墨烯上TMDs的存在实际上抑制了石墨烯本身的电容性能。
