Efficient and long-term photocatalytic H2 evolution stability enabled by Cs2AgBiBr6/MoS2 in aqueous HBr solution

Abstract

Lead-free Cs 2 AgBiBr 6 (CABB) double perovskite as a new-type photocatalytic material alternative to lead halide perovskites holds promise to implement the solar-H 2 conversion, but the interior recombination of photo-generated carriers and thus low photocatalytic hydrogen evolution reaction (HER) rate of CABB restrict its further industrial applications. Herein, we report the composite fabrication of MoS 2 /CABB heterostructure for high-efficiency and durable photocatalytic HER by anchoring non-noble MoS 2 onto CABB via a facile dissolution-recrystallization method. The optimized MoS 2 /CABB performs a visible-light HER rate of 87.5 μmol h −1 g −1 in aqueous HBr solution, ca. 20-fold compared to that of pure CABB (4.3 μmol h −1 g −1 ), and presents a discontinuous 500-h photocatalytic HER stability with no evident loss. The superb performance of MoS 2 /CABB can be ascribed to the kinetics-facilitated heterostructure consisting of stable CABB and MoS 2 . This work proposes a facile and versatile tactic to construct a low-cost Cs 2 AgBiBr 6 -based heterostructure for efficient and long-term photocatalytic HER. • Lead-free CABB/MoS 2 are prepared by a facile dissolution-recrystallization method. • CABB/MoS 2 achieves boosted charge transfer by the constructed heterostructure. • CABB/MoS 2 owns both high visible-light HER rates and long-term stability. • CABB/MoS 2 exhibits superb photocatalytic HER stability during 500-h cyclic test.