pH-Responsive Flexible Copper Electrode with Switchable Wettability for Electrocatalytic Hydrogen/Oxygen Evolution Reactions and Urea Oxidation Reaction

ACS Appl Mater Interfaces. 2023 Jun 7;15(22):27357-27368. doi: 10.1021/acsami.3c03934. Epub 2023 May 23.

Abstract

The development of a pH-responsive electrode with switchable wettability is of great importance in water electrolysis. Here, we designed a pH-responsive copper mesh/copolymer electrode to eliminate the adhesion of hydrogen/oxygen bubbles under high-speed water electrolysis by adjusting the wettability of the electrode surface. Furthermore, the kinetics of water oxidation and urea oxidation reactions on the as-prepared copper mesh/copolymer electrode were explored. Most noteworthy, the flexible water electrolysis performance of the as-prepared pH-responsive electrode was investigated for the first time. The results indicate that the copper mesh/copolymer electrode accelerates the hydrogen evolution reaction, oxygen evolution reaction, and urea oxidation reaction under better surface wettability, while it inhibits these reactions under poor surface wettability. The results provide insight into the development of unusual water electrolyzers with different pH electrolytes and the design of water electrolysis electrodes.

Keywords: flexible electrode; gas diffusion electrode; pH-responsive electrode; water oxidation; wettability.