▎ 摘　　要

NOVELTY - Three-dimensional nitrogen-doped graphene/gamma-iron oxide ( gamma -Fe2O3)/silver (Ag) composite photocatalyst includes a three-dimensional nitrogen-doped graphene/ gamma -Fe2O3 composite material, and Ag nanoparticles supported on the composite material. The three-dimensional nitrogen-doped graphene/ gamma -Fe2O3/Ag composite photocatalyst has a three-dimensional network structure. The mass ratio of the nitrogen-doped graphene to the gamma -Fe2O3 particles is 1:0.5-2. The loading amount of the Ag nanoparticles is 10-30 wt.%. USE - Three-dimensional nitrogen-doped graphene/ gamma -Fe2O3/Ag composite photocatalyst used in the photocatalytic degradation of dyes (claimed). ADVANTAGE - The three-dimensional nitrogen-doped graphene/ gamma -Fe2O3/Ag composite photocatalyst adopts visible light-responsive gamma -Fe2O3 as a semiconductor photocatalyst and graphene oxide as a carrier, and after nitrogen doping and precious metal silver deposition are modified, a nitrogen-doped graphene/ gamma Fe2O3/Ag composite photocatalyst with a three-dimensional structure is obtained through reactive self-assembly. The catalyst has a larger specific surface area and enhances the adsorption effect, and the electron transport efficiency is higher, which can effectively inhibit the recombination of photo-generated electron-hole pairs, and at the same time has magnetic responsiveness and is easy to recycle. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing three-dimensional nitrogen-doped graphene/ gamma -Fe2O3 composite material, which involves dispersing graphene oxide in a liquid medium, adding urea, mixing uniformly, and then adding gamma -Fe2O3 particles and dodecane sodium benzene sulfonate, continue to mixing uniformly, and then reacting at 160-190 degrees C for 10-15 hours to obtain the three-dimensional nitrogen-doped graphene/ gamma -Fe2O3 composite material.