Wu Xiujuan, Zhao Yimeng, Xing Tongyu, Zhang Peili, Li Fusheng, Lee Husileng, Li Fei, Sun Licheng
State Key Laboratory of Fine Chemicals, DUT-KTH Joint Education and Research Center on Molecular Devices, Dalian University of Technology (DUT), Dalian, 116024, PR China.
Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, 10044, Sweden.
ChemSusChem. 2018 Jun 11;11(11):1761-1767. doi: 10.1002/cssc.201800407. Epub 2018 May 2.
A simple and low-cost fabrication method is needed to obtain effective and robust heterogeneous catalysts for the oxygen evolution reaction (OER). In this study, an electrocatalyst FeNiO H with a hierarchical structure is synthesized on nickel foam by a simple fabrication method through anion exchange from a metal phosphate to a metal hydroxide. The as-fabricated FeNiO H electrode requires overpotentials of 206 and 234 mV to deliver current densities of 10 and 50 mA cm , respectively. The catalytic performance of FeNiO H is superior to that of most previously reported FeNi-based catalysts, including NiFe layered double hydroxide. The catalyst also shows good long-term durability at a current density of 50 mA cm over 50 h with no activity decay under 1 m KOH. By comparison to the directly electrodeposited FeNi hydroxide in morphology and electrochemical properties, the improved activity of the catalyst could be mainly attributed to an enhancement of its intrinsic activity, which was caused by the anion exchange of phosphate to (oxy)hydroxide. Further studies by cyclic voltammetry indicated a stronger interaction between Ni and Fe from the negative shift of the oxidation peak of Ni /Ni in comparison with reported FeNiO H , which promoted the generation of active Ni species more easily. This work may provide a new approach to the simple preparation of effective and robust OER catalysts by anion exchange.
需要一种简单且低成本的制备方法来获得用于析氧反应（OER）的高效且稳定的非均相催化剂。在本研究中，通过一种简单的制备方法，通过从金属磷酸盐到金属氢氧化物的阴离子交换，在泡沫镍上合成了具有分级结构的电催化剂FeNiO H。制备的FeNiO H电极分别需要206和234 mV的过电位来提供10和50 mA cm 的电流密度。FeNiO H的催化性能优于大多数先前报道的FeNi基催化剂，包括NiFe层状双氢氧化物。该催化剂在50 h内50 mA cm 的电流密度下也表现出良好的长期耐久性，在1 m KOH下没有活性衰减。通过与直接电沉积的FeNi氢氧化物的形貌和电化学性质进行比较，催化剂活性的提高主要归因于其本征活性的增强，这是由磷酸盐向（氧）氢氧化物的阴离子交换引起的。循环伏安法的进一步研究表明，与报道的FeNiO H相比，Ni /Ni氧化峰的负移表明Ni和Fe之间的相互作用更强，这更容易促进活性Ni物种的生成。这项工作可能为通过阴离子交换简单制备高效且稳定的OER催化剂提供一种新方法。
