Efficient hydrogen generation of indium doped BaTiO3 decorated with CdSe quantum dots: Novel understanding of the effect of doping strategy

Abstract Doping has been widely utilized as an effective method of semiconductor modification to enhance photocatalytic efficiency. Most researches focus only on the effect of doping on decreasing band gap and inhibiting carriers recombination, however, the proximity of conduction band minimum (CBM) and valence band maximum (VBM) indicates the decrease of energy level and redox potential. Therefore, to further investigate the effect of doping on photocatalytic activity, the composite structure consisted of CdSe quantum dots (QDs) and indium doped BaTiO 3 is synthesized by plain hydrothermal and chemical bath means. Under the condition of maintaining CdSe QDs optimal load ratio of 7.5 mol.%, doping 2.5% indium maximizes hydrogen production (0.437 mmol g –1  h –1 ) compared to undoped composite structure (0.258 mmol g –1  h –1 ), which originates from the increase of photo-induced electron reductive activity. The results suggest that we can use doping in reverse thinking to provide a new tactics for the design of semiconductor photocatalytic materials.