摘要
of main observation and conclusion The heterojunction-type structure has shown significant merits in tuning the optical properties and carrier physics.Inspired by the excellent absorption capability of halide perovskite materials for visible light,a series of CsPbBr3/TiO2 heterojunction-type photocatalysts with various all-inorganic-perovskite/TiO2 ratios are successfully fabricated by the ligand-assisted reprecipitation(LARP)method.The heterojunction structure extends the light absorption of TiO2 with good chemical and structural stability.A Pb-O interaction at the CsPbBr3/TiO2 interface is observed by the XPS and confirmed by the TRPL showing improved interface carrier transport and stability.The heterojunction-type catalyst shows drastically enhanced photocatalytic activity towards the direct oxidation of toluene with 02 molecule,as an important reaction for organic chemical synthesis.The optimized sample shows an activity of 2356μmol·g^-1·h^-1 at 75℃,4 times of that of the naked CsPbBr3 nanocrystals,and 3 times of that of the bare TiO2.Based on the investigation with trapping agents,a reaction mechanism is hence proposed suggesting that the photo-generated hole may be involved in the rate-limiting step.This work demonstrates the potential of inorganic halide perovskite-based heterojunction structure for photocatalytic applications.
基金
This work is financially supported by the National Natural Science Foundation of China(21975028,51673025)
National Key Research and Development Program of China(2016YFBO700700)
the start-up funding of BIT.
