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

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.