Co-Cu-P nanosheet-based open architecture for high-performance oxygen evolution reaction

Abstract

The exploration of earth-abundant electrocatalysts and insight on the relationship between their activity and structure is challenging for large-scale electrochemical water oxidation. Herein, 2D Co-Cu-P nanosheets on Ni foam are fabricated by electrodeposition and subsequent phosphorization process. The Co-Cu-P nanosheets are highly interconnected to form an open-structured hierarchical network structure, which endows the product large surface area, efficient mass transportation, and fast gas releasing. In addition, the surface of Co-Cu-P would rapidly convert into hydroxides layer in the earlier oxygen evolution reaction (OER) process, which preserves the Co-Cu-P phosphide inside and serves as the real active sites for OER process. Benefiting from the rationally designed open-structured hierarchical network and the synergistic effect from the two kinds of metal cations with high conductivity, the resultant Co-Cu-P bimetal phosphide open-structured network delivers superb OER performance with an overpotential of 240 mV to drive a current density of 10 mA cm −2 in alkaline medium, outperforming the performance of the Co-P and Cu 3 P monometallic phosphide counterpart. This work provides a simple synthesis approach to construct bimetal phosphide with a rationally designed open-structured hierarchical network toward boosting electrocatalytic OER performance.

Methionine-assisted electrodeposition of porous copper cobalt bi-metallic hetero-nanostructures on an indium tin oxide electrode: a disposable and stable electrode for non-enzymatic glucose sensing

“…The produced hydroxyl ions increase the local pH around the electrode and the hydroxyl ions react spontaneously with metal ions and form the metal hydroxides on the electrode surface, as depicted in eqn (1)–(3). 28 Co(NO 3 ) 2 → Co 2+ + 2NO 3 − NO 3 − + 7H 2 O + 8e − → NH 4 − + 10OH − Cu 2+ + Co 2+ + 4OH − → CuCo(OH) 4 …”