摘要
Metal halide perovskites have emerged as novel and promising photocatalysts for hydrogen generation.Currently,their stability in water is a vital and urgent research question.In this paper a novel approach to stabilize a bismuth halide perovskite[(CH_(3))_(2)NH_(2)]_(3)[Bil_(6)](DA_(3)Bil_(6))in water using dimethylammonium iodide(DAI)without the assistance of acids or coatings is reported.The DA3Bil6 powder exhibits good stability in DAI solutions for at least two weeks.The concentration of DAI is found as a critical parameter,where the I^(-)ions play the key role in the stabilization.The stability of DA3Bil6 in water is realized via a surface dissolution-recrystallization process.Stabilized DA3Bil6 demonstrates constant photocatalytic properties for visible light-induced photo-oxidation of I^(-)ions and with PtCI4 as a co-catalyst(Pt-DA_(3)Bil_(6)),photocatalytic H2 evolution with a rate of 5.7μmol·h^(-1)from HI in DAI solution,obtaining an apparent quantum efficiency of 0.83%at 535 nm.This study provides new insights on the stabilization of metal halide perovskites for photocatalysis in aqueous solution.
基金
the Kvantum Institute Em erging Project at the University of Oulu and Academy of Finland ELECTRA-project(No.2430291511).We thank Raija Oilunkaniemi and idarkus Riihimaki for the help with XRD and ATR characterization,respectively.We are grateful to the staff from Centre for Material Analysis(University of Oulu)for the characterization.ELI-ALPS is supported by the European Union and co-flnanced by the European Regional Development Fund(No.GINOP-2.3.6-15-2015-00001).M.U.K.also acknow ledgesfundingfrom PaNOSC Europeanproject.
