Self-Supported Electrocatalysts for Efficient Oxygen Evolution Reaction: Hierarchical CuOx@CoO Nanorods Grown on Cu Foam

Graphical The center of attention : The CuO x @CoO nanorods grown on Cu Foam with the hierarchical configuration and the heterojunction interfaces enjoyed a couple of advantages of self-supported electrodes: needing no glue as an electrode, avoiding the agglomeration of MOFs-based particles, and forming the outward active figuration and large specific surface area. Those features lead to superior OER performances. 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.