Preparation method and application of Z-type alpha-Fe2O3/g-C3N4 composite photocatalyst

The invention relates to a preparation method of a direct Z-type alpha-Fe2O3/g-C3N4 photocatalyst, the direct Z-type alpha-Fe2O3/g-C3N4 photocatalyst is used as an efficient visible light photocatalyst, the catalyst has good stability, and the preparation method comprises the following steps: (1) preparing alpha-Fe2O3 by a hydrothermal method; and (2) taking a certain amount of alpha-Fe2O3 nanoparticles and an organic nitrogen source through a high-temperature calcination method, and carrying out high-temperature calcination to obtain the alpha-Fe2O3/g-C3N4 Z-type photocatalyst. The novel Z type photocatalyst of alpha-Fe2O3/g-C3N4 has good catalytic activity for the oxidative coupling reaction of primary amine. The improvement of the photocatalytic performance of the g-C3N4 is derived from a unique Z-type structure, electrons accumulated in a conduction band CB of the g-C3N4 show high reduction ability under the irradiation of visible light, O2 can be reduced into. O2 , the reaction rate of a primary amine