Next-generation photocatalytic system: Ga2O3-modified Ga Nanoislands on graphene for H2 production

Abstract

Study investigates Ga2O3/Ga on Graphene/SiO2/Si, prepared via temperature-controlled growth of Ga, for photocatalytic hydrogen generation, marking the first exploration of this system for such purpose. Thin surface ultra-wide band gap Ga2O3 layer effectively photoemits electron-hole pairs under UVC and the metallic Ga cores enhance electric field separating charge carriers by formation of localized surface plasmon (LSP) resonances. These effects increase hydrogen yields. Computational analysis of LSP-induced electric field enhancement quantitatively supports proposed fundamental mechanism underlying sample's photoactivity. The most active photocatalyst (Ga-M) with medium-size Ga particles (radius 14 nm) exhibited ten thousand times higher activity per gram than commercial TiO2.