Ameliorating the carrier dynamics behavior via plasmonic Ag-modified CuBi2O4 inverse opal for the efficient photoelectrocatalytic reduction of CO2 to CO

Low light absorption efficiency and short carrier diffusion length mainly restrict the use of CuBi 2 O 4 as a photocathode for an efficient photoelectrocatalytic CO 2 reduction reaction (PEC-CO 2 RR). These inadequacies are alleviated by fabricating CuBi 2 O 4 inverse opal photocathode modify with plasmonic Ag nanoparticles (CuBi 2 O 4 IOs-Ag) by using a sacrificing template method. The CuBi 2 O 4 IOs-Ag photocathode exhibits superior PEC-CO 2 RR-to-CO performance with a Faraday efficiency (FE) of 92% at 0.2 V versus reversible hydrogen electrode, and this value is roughly 1.6 times that of the pristine CuBi 2 O 4 thin film. Detail characterization and experiments reveal that the exceptional three-dimensional (3D) order structure simultaneously accelerates the mass transfer rates and enhances the light-harvesting efficiency. In addition, the introduction of Ag nanoparticles remarkably improves the surface charge distribution by forming an ohmic contact with CuBi 2 O 4 . Consequently, carrier recombination is efficiently inhibited, and the carrier dynamics behavior is improved. This work provides important insights into the design of high-performance photoelectrocatalytic systems for CO 2 reduction by engineering the microstructure of catalysts with localized surface plasmon resonance effect.