To further promote the photocatalytic performance of g-C3N4,TiO2 quantum dots were loaded on g-C3N4 by a pore impregnating method.The results show that the TiO2 quantum dots modification significantly influences the XRD patterns,surface parameters,particle size distribution and the visible light adsorption of g-C3N4.Using Rhodamine B as a simulated pollutant,the photocatalytic activity of obtained TiO2/g-C3N4 was evaluated under a simulative sunlight irradiation.It is indicated that all the composites with TiO2 quantum dots modification exhibit higher photocatalytic performance than the pristine g-C3N4.When the mass ratio of TiO2/g-C3N4 is 3%,the composite displays the highest photocatalytic activity.The trapping experiments show that ·O2- is the main active free species for the photocatalytic decolorization reaction.