In this study, TiO 2 /CQDs(TC), TiO 2 /BiOI(TB), TiO 2 /BiOI/CQDs(TBC) were prepared via a step-by-step method. Photocatalytic properties of the samples were carried out under visible-light irradiation using methyl orange (MO) as the target molecular. Among the samples, TBC showed the best photocatalytic performance, and the photocatalytic efficiency of TBC was more than 2 times higher than that of TiO 2 , TC and TB samples, respectively. The reasons for the improved photocatalytic performance were discussed in this paper. [ABSTRACT FROM AUTHOR]