Muthurasu Alagan, Dahal Bipeen, Chhetri Kisan, Kim Hak Yong
Department of BIN Convergence Technology, Jeonbuk National University, Jeonju 561-756, Republic Korea.
Department of Organic Materials and Fiber Engineering, Jeonbuk National University, Jeonju 561-756, Republic of Korea.
Inorg Chem. 2020 Mar 16;59(6):3817-3827. doi: 10.1021/acs.inorgchem.9b03466. Epub 2020 Feb 24.
The development of bifunctional, highly active electrocatalysts for an overall water splitting reaction remains a major challenge. Here, the sacrificial template-assisted transformation of cobalt hydroxide nanowire (Co(OH) NW) into a metal-organic framework network (MOF) is conceived as a porous structure that provides extremely active and durable electrochemical energy conversion characteristics. After this, the 1D MOF modified Co NWs can be further transformed into a hybrid structure (MOF CoSeO NWs) by selenization. The self-template transformation strategy allows the interconnected porous conductive network to be exposed to abundant reactive sites and to improve electronic conductivity/structural integrity. Thus, the obtained catalyst established by electrocatalytic activity in the course of the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) in 1 M KOH solution requires overpotentials (η) of 290 and 150 mV to achieve a current density of 50 and 10 mA cm for both OER and HER. Interestingly, as a full cell water electrolyzer (MOF CoSeO NWs (+) // MOF CoSeO NWs (-)), the MOF CoSeO NW's modified electrode exhibits an affordable cell voltage of 1.675 V at a current density of 100 mA cm. This work involves a viable and systematic strategy to prepare many other functional integrated MOFs that can be used for energy storage and conversion in multiple applications.
开发用于全水解反应的双功能、高活性电催化剂仍然是一项重大挑战。在此，将氢氧化钴纳米线（Co(OH) NW）通过牺牲模板辅助转化为金属有机框架网络（MOF）被设想为一种多孔结构，其具有极其活跃且持久的电化学能量转换特性。在此之后，一维MOF修饰的Co NWs可通过硒化进一步转化为混合结构（MOF CoSeO NWs）。这种自模板转化策略使相互连接的多孔导电网络暴露于大量活性位点，并提高电子导电性/结构完整性。因此，在1 M KOH溶液中通过析氧反应（OER）和析氢反应（HER）的电催化活性所制备的催化剂，对于OER和HER而言，要达到50和10 mA cm的电流密度分别需要290和150 mV的过电位（η）。有趣的是，作为全电池水电解槽（MOF CoSeO NWs(+) // MOF CoSeO NWs(-)），MOF CoSeO NW修饰电极在100 mA cm的电流密度下表现出1.675 V的可承受电池电压。这项工作涉及一种可行且系统的策略，可用于制备许多其他功能性集成MOF，这些MOF可用于多种应用中的能量存储和转换。
