To completely utilize the high redox ability of photo-induced charge carriers. Here, a Z-scheme photocatalyst of TiO2 QDs/Bi12TiO20 (TBT) composites with TiO2 QDs fragment attached to the surface of Bi12TiO20 (BTO) was prepared and the photocatalytic activity was evaluated by degradation of gatifloxacin (GF). The optimal photocatalytic performance of TBT displayed 3 times higher than bare BTO. The improved photocatalytic performance was ascribed to the effective separation of the charge carriers between TiO2 QDs and BTO via the direct Z-scheme heterojunction. Such a strategy for the construction of Z-scheme TBT composites for removal of organic pollutants, proving new insights into design photocatalyst. (C) 2019 Elsevier Ltd. All rights reserved.