Highly Active Cobalt–Copper–Selenide Electrocatalysts for Solar-Driven Oxygen Evolution Reaction: An Electrochemical Activation Energy Aspect

Abstract

Effective electrocatalysts with high activity for oxygen evolution reactions (OER) play a crucial role in generating environmentally and sustainable hydrogen fuel via electrolysis. Currently, most highly active electrocatalysts are synthesized through complex multisteps and high-temperature heat treatments, which limit their industrial applications. Herein, we developed a cobalt−copper−selenide (Co-CuSe) electrocatalyst for the OER via simple electrodeposition and a hydrothermal method. CoCuSe showed exceptional OER activity by forming highly active oxyhydroxide species through surface reconstruction. In particular, CoCuSe demonstrated a significant reduction in the activation barrier for OER despite exhibiting the same OER mechanism as CoCu(OH) 2 and thus improved OER activity. Furthermore, when utilizing CoCuSe in conjunction with an industrial crystalline silicon solar cell, the alkaline water electrolyzer effectively produced hydrogen energy in the presence of natural light, demonstrating a solar-to-hydrogen efficiency of around 13.0%. This research suggests that the remarkable activity of transition metal selenides results from a reduced activation barrier for OER.

Optimized Adsorption–Catalytic Conversion for Lithium Polysulfides by Constructing Bimetallic Compounds for Lithium–Sulfur Batteries

“…All authors have read and agreed to the published ver- In addition to being used in Li-S batteries, bimetallic selenides can also be used in other types of batteries (lithium-ion batteries, sodium-ion batteries, magnesium-ion batteries, et al), various supercapacitors, electrocatalysts for hydrogen evolution reaction, oxygen evolution reaction, etc. [51][52][53][54][55][56][57]. Therefore, the designed bimetallic selenides in this paper can also be extended to other fields.…”