Band-Gap Tunable 2D Hexagonal (GaN)1–x(ZnO)x Solid-Solution Nanosheets for Photocatalytic Water Splitting

A (GaN)1–x(ZnO)x solid solution as a promising visible-light-driven photocatalyst for overall water splitting has attracted extensive attention. In this work, we proposed a template reactive strategy toward the synthesis of band-gap tunable 2D (GaN)1–x(ZnO)x nanosheets as thin as 14 nm to reduce the carrier transportation path and thus efficiently decrease the recombination of electrons and holes. It is demonstrated that the template strategy enables an ideal morphology and structure transformation from hexagonal 2D ZnGa2O4 nanosheets to 2D (GaN)1–x(ZnO)x nanosheets in the nitridation process. After the modification of 1 wt % of Rh cocatalyst, the flowerlike (GaN)0.89(ZnO)0.11 nanosheets show an enhanced hydrogen evolution in pure water (pH 4.5).