Enhancement of photocatalytic hydrogen production of semiconductor by plasmonic silver nanocubes under visible light

A pivotal factor limiting the photocatalytic efficiency of water splitting is the high charge-carrier recombination rate in the photocatalyst. Here, we demonstrate this issue can be relieved by combining photocatalyst with a plasmonic metal. We introduced organic molecule capped silver nanocubes (Ag NCs) to Rh2−yCryO3/GaN:ZnO (host photocatalyst: GaN:ZnO, hydrogen production cocatalyst: Rh2−yCryO3) and showed that the Ag NCs improved the photocatalytic water splitting efficiency. Finite difference time domain simulations suggested this improvement can be ascribed to efficient photon scattering and intense local electric field by the localized surface plasmon resonance of Ag NCs. The Ag-Rh2−yCryO3/GaN:ZnO composite exhibited high photochemical stability due to the protection of Ag NCs by the organic surfactant.