Au-Decorated CoOOH Nanoplate Hierarchical Hollow Structure for Plasmon-Enhanced Electrocatalytic Water Oxidation

The development of efficient oxygen evolution reaction (OER) catalysts is essential for the generation of renewable hydrogen. Cobalt-based catalytic material has been widely studied as a very promising metal catalyst. However, it is difficult for single simple-type cobalt-based catalysis to meet the requirement of activity. Composite material and auxiliary methods have been used to improve catalytic activity. Herein, a gold-nanoparticle-decorated CoOOH nanoplate hierarchical hollow structure (Au/CoOOH) is designed to improve the electro-catalytic performance of water oxidation. Moreover, a photoinduced surface plasmon excited on gold nanoparticles is also introduced to further enhance the photoassisted OER activity. The synergy of Au and CoOOH improves the charge excitation and transfer, which increase the number of active sites markedly. A high turnover frequency (3.75 s(-1) at an overpotential of 360 mV) and a low overpotential of 290 mV at a current density of 10 mA cm(-2) have been achieved with the assistance of a laser. Furthermore, the monochromatic incident photon-to-electron conversion efficiency (IPCE) can reach up to 5%.