Spontaneous Synthesis of Silver-Nanoparticle-Decorated Transition-Metal Hydroxides for Enhanced Oxygen Evolution Reaction.

The fabrication of metal-supported hybrid structures with enhanced properties typically requires external energy input, such as pyrolysis, photolysis, and electrodeposition. In this study, silver-nanoparticle-decorated transition-metal hydroxide (TMH) composites were synthesized by an approach based on a spontaneous redox reaction (SRR) at room temperature. The SRR between silver ions and TMH provides a simple and facile route to establish effective and stable heterostructures that can enhance the oxygen evolution reaction (OER) activity. Ag@Co(OH)x grown on carbon cloth exhibits outstanding OER activity and durability, even superior to IrO2 and many previously reported OER electrocatalysts. Experimental and theoretical analysis demonstrates that the strong electronic interaction between Ag and Co(OH)2 activates the silver clusters as catalytically OER active sites, effectively optimizing the binding energies with reacted intermediates and facilitating the OER kinetics.