High quality ternary-alloyed CdTeSe quantum dots (QDs) have been synthesized via a simple one-pot approach in aqueous phase. CdTeSe QDs show an average size of 3.0 nm with good crystallinity, excellent monodispersity and relatively narrow size distribution. TiO2 nanotubes (TNTs) were prepared by hydrothermal method with larger specific surface area (364.2 m(2) g(-1)), and CdTeSe@TNTs were synthesized by in situ process. The absorption edge of CdTeSe@TNTs is red shifted significantly toward 697 nm. After sensitized with CdTeSe, the photoluminescence (PL) emission of CdTeSe@TNTs is significantly quenched, and the fluorescence lifetime of the composites is drastically decayed from 105.82 ns to 0.13 ns with a high photoinduced electron transfer rate (k(et) = 7.98 x 10(9)s(-1)) because of their high matchable lattice constant. In addition, under visible-light irradiation, the photocatalytic efficiency of rhodamine B (RhB) with CdTeSe@TNTs reaches 90% for 80 min. And the photocatalytic reaction rate constant for CdTeSe@TNTs is 0.0272 min(-1), which is 5.4 and 3.4 times larger than that of pure TNTs and CdTeSe QDs, respectively. It is due to the broad visible absorption of CdTeSe@TNTs and the faster photoinduced electron transfer from CdTeSe QDs to TNTs. (C) 2016 Elsevier B.V. All rights reserved.