Abstract：The TiO2/g-C3N4 composites were prepared by the hydrothermal method with cetyltrimethyl ammonium bromide (CTAB). The influence of CTAB on the structural properties and spectral properties of the composites was studied. The samples were characterized by XRD, TEM, N2 adsorption-desorption, FT-IR, UV-Vis DRS and PL, meanwhile, the samples were used to degrade unsymmetrical dimethyl hydrazine (UDMH) wastewater under visible light. The results show that the crystal structure of TiO2/g-C3N4 composites assisted by CTAB is intact,with smaller particle size of nanoparticles and uniformly distributed on g-C3N4 sheets. The specific surface area of the composites increases and the mesoporous is more abundant, the adsorption ledge of the composites is expanded to 450nm, the recombination rate of hole-electron reduces obviously. Photocatalytic results show that the UDMH degradation efficiency of TiO2/g-C3N4 (CTAB) reaches 83.2% in 120min, which is improved by 13.7% than that of the no CTAB-assisted composites.
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