Self‐Supported Electrocatalysts for Efficient Oxygen Evolution Reaction: Hierarchical CuO<sub>x</sub>@CoO Nanorods Grown on Cu Foam
Li Pan, Jianzhi Wang, Ning Cai, Lei Wang, Jing Tong, Faquan Yu
Abstract
Abstract The fabrication of cost‐effective and performance‐advanced electrocatalysts is in great requirements for water splitting to achieve sustainable oxygen production. A simple and effective precursor of ZIF‐67 particles mounted on Cu(OH) 2 nanorods was induced by a template alignment method. After annealing, hierarchical CoO polyhedron‐decorated CuO/Cu 2 O (CuO x ) nanorods on Cu foam (denoted as CuO x @CoO NRs/CF) were achieved, which displayed the heterojunction in CuO x components, hierarchical configuration and outward active sites. These features, verified by HRTEM, SEM, XPS and EDX, optimized the oxygen evolution reaction (OER) electrocatalyst. Benefiting from its large electrochemical surface area and the synergetic effect between CuO x and CoO, CuO x @CoO NRs/CF exhibited considerable catalytic activity with a low overpotential of 254 mV to obtain a current density of 10 mA cm −2 in alkaline electrolyte and a scarce loss of the initial catalyst activity over 24 h and over 5000 cycles. This work provides a channel to enhance the performance in OER.