Li Wei, Feng Bomin, Yi Lingya, Li Junying, Hu Weihua
Key Laboratory of Luminescence Analysis and Molecular Sensing, Southwest University, Ministry of Education, 2 Tiansheng, Beibei, Chongqing, 400715, P. R. China.
School of Materials and Energy, Southwest University, Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies, 2 Tiansheng, Beibei, Chongqing, 400715, P. R. China.
ChemSusChem. 2021 Jan 21;14(2):730-737. doi: 10.1002/cssc.202002509. Epub 2020 Nov 24.
Active electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are decisive for achieving efficient energy conversion from electricity to hydrogen fuel through water electrolysis. In this study, tremella-like Ru-doped Co-V layered double hydroxide nanosheets on Ni Foam (Ru-CoV-LDH@NF) was fabricated by a one-pot solvothermal reaction. As-prepared Ru-CoV-LDH@NF, with a nominal Ru loading of around 51.6 μg cm exhibits excellent bifunctional catalytic activity towards HER and OER in alkaline media. To accomplish a current density of 10 mA cm , it demands 32 mV and 230 mV overpotentials for HER and OER, respectively. The alkali electrolyzer utilizing Ru-CoV-LDH/NF as bifunctional electrocatalyst affords 10 mA cm electrolytic current density at an extremely low cell voltage of 1.50 V, showing excellent performance compared to a Pt/C-RuO -based electrolyzer and many other bifunctional electrocatalyst-based ones. The incorporation of Ru changes the morphology of the resultant nanosheets to offer high electrochemical surface areas for electrocatalysis; at the same time, it significantly boosts the intrinsic HER/OER electrocatalytic activity. For HER, the energy barrier of the Volmer step is efficiently reduced upon Ru doping, whereas the Ru dopants optimize the absorption strength of *O intermediates to facilitate the OER process. This work offers a feasible means to optimize the Co-based hydroxide materials for improved electrocatalysis in overall water splitting.
用于析氢反应（HER）和析氧反应（OER）的活性电催化剂对于通过水电解实现从电到氢燃料的高效能量转换起着决定性作用。在本研究中，通过一锅溶剂热反应在泡沫镍上制备了类银耳状Ru掺杂的Co-V层状双氢氧化物纳米片（Ru-CoV-LDH@NF）。所制备的Ru-CoV-LDH@NF，其名义Ru负载量约为51.6 μg cm，在碱性介质中对HER和OER表现出优异的双功能催化活性。为了实现10 mA cm的电流密度，HER和OER分别需要32 mV和230 mV的过电位。使用Ru-CoV-LDH/NF作为双功能电催化剂的碱性电解槽在极低的1.50 V电池电压下提供10 mA cm的电解电流密度，与基于Pt/C-RuO的电解槽和许多其他基于双功能电催化剂的电解槽相比，表现出优异的性能。Ru的掺入改变了所得纳米片的形态，为电催化提供了高电化学表面积；同时，它显著提高了HER/OER的本征电催化活性。对于HER，Ru掺杂后Volmer步骤的能垒有效降低，而Ru掺杂剂优化了*O中间体的吸附强度，以促进OER过程。这项工作提供了一种可行的方法来优化钴基氢氧化物材料，以改善全水分解中的电催化性能。
