The preparation of Al2O3/g-C3N4 composites in aluminum–water self-assembly system and its improved photocatalytic properties

Abstract

The aluminum alloy is used as the aluminum source, together with melamine and cyanuric acid, in a water reaction system to obtain the precursor of Al₂O₃/g-C₃N₄ through self-assembly in one step, and then calcined to obtain the Al₂O₃/g-C₃N₄ composite photocatalytic material. γ-Al₂O₃ has a defect site that can accept g-C₃N₄ electrons and can bind well with g-C₃N₄. The addition of γ-Al₂O₃ changed the morphology of g-C₃N₄ into a damaged tubular structure with many irregular pores. Also, the specific surface area increased to about 1.2 times that of g-C₃N₄, and the light absorption edge was extended to 500 nm. In addition, the position of the valence band of g-C₃N₄ was also changed. Compared with g-C₃N₄, Al₂O₃/g-C₃N₄ has better photocatalytic performance, and the degradation rate of dye rhodamine B (RhB) is about 1.70 times that of g-C₃N₄.