MOF-Derived Iron–Cobalt Bimetallic Selenides for Water Electrolysis with High-Efficiency Oxygen Evolution Reaction
Jiangning Li, Qianyun He, Yichao Lin, Lei Han, Kai Tao
Abstract
Highly active and stable oxygen evolution reaction (OER) electrocatalysts for water electrolysis are currently in high demand. Herein, a rationally designed three-dimensional (3D) CoFe selenide porous array (Fe–CoSe PA) is synthesized through ion exchange from zeolitic imidazolate framework-L (ZIF-L) nanoarray, followed by a facile selenization under hydrothermal conditions for OER electrocatalysis. During the OER process, the surface of Fe–CoSe PA is rapidly oxidized to CoFe oxides/hydroxides, which prevents the inner layer from being oxidized. Benefiting from the high porosity, abundant active sites, and the high conductivity of inner Fe–CoSe, Fe–CoSe PA exhibits excellent OER performance, with an overpotential of 285 mV at a current density of 10 mA cm–2, and a small Tafel slope of 68 mV dec–1, as well as high stability under 50 h of continuous testing. The present work could provide a facile route for fabricating 3D porous selenides for highly efficient OER catalysis.