▎ 摘　　要

TiO2/graphene composite was synthesized in the vapor environment of isopropanol. In order to improve the properties of composite, N-doped of TiO2/graphene with different N/Ti molar ratio was prepared in the vapor environment of deionized water and used urea as the source of nitrogen. The N-doped occupies in the interstitial sites of TiO2 lattice, substitutes for O element in TiO2 and for C element in graphene, and simultaneously changes the chemical states of Ti and O elements in TiO2. N-doped changes the morphology of TiO2 from nano-sheets to nanoparticles, accompanying with the decrease in specific surface area of the composites, first increases the particle size of TiO2 and then decreases, and alters the vibration modes of Ti-O-Ti. The composite with R-N/Ti=2 exhibits the enhanced photocatalytic degradation performance to methylene blue, and the degradation rate increases from 7.7x10(-2) min(-1) for the undoped composite to 9.6x10(-2) min(-1).