Space-confined growth of lead-free halide perovskite Cs3Bi2Br9 in MCM-41 molecular sieve as an efficient photocatalyst for CO2 reduction at the gas-solid condition under visible light

A facile and effective impregnation method is employed to synthesize the space-confined growth of lead-free halide perovskite Cs3Bi2Br9 in MCM-41 molecular sieve. This MCM-41 @CBB (Cs3Bi2Br9) composite shows an outstanding performance for the photocatalytic reduction of CO2 to CO at the gas-solid condition under visible light irradiation. The CO production rate of the MCM-41 @ 50 wt% CBB is determined to be 17.24 mu mol g(-1) h(-1), which greatly exceeds that of pure CBB (1.89 mu mol g-1 h-1). The composite is highly stable showing no apparent decrease in the catalytic activity after 8 cycles of repeated experiment. The performance of space-confined growth of CBB nanoparticles in the serial molecular sieve exhibits 2.97-13.4 fold higher than that of pure CBB, respectively, which is superb than CPB (CsPbBr3) and MCM-41 @CPB prepared in the same condition. The results are comparable with those reported for many lead halide perovskites, and are in the top among the leadfree perovskites, especially bismuth halide perovskites.

Automated summary

A facile and effective impregnation method was used to synthesize lead-free halide perovskite Cs3Bi2Br9 in MCM-41 molecular sieve. The resulting composite showed outstanding photocatalytic activity for the reduction of CO2 to CO under visible light irradiation. The composite exhibited significantly higher CO production rate compared to pure CBB, and maintained stable catalytic activity after repeated experiments. The performance of the composite was superior to other perovskites, especially bismuth halide perovskites.