Continuously enhanced photoactivity of hierarchical β-Bi2O3/Bi2S3 heterostructure derived from novel BiO2CH3 octagonal nanoplates

Abstract BiO 2 CH 3 nanoplate, a new organometallic crystal, with octagonal morphology is successfully prepared using methanol solvothermal method and further employed as template to fabricate porous β-Bi 2 O 3 octagonal nanoplates with a thickness of less than 50 nm. Then a series of hierarchical octagonal haystack-like β-Bi 2 O 3 /Bi 2 S 3 hybrids with large heterointerface and small bandgaps (1.36–1.44 eV) are constructed. It is found that, different from many regular photocatalysts that suffer from shrink of photocatalytic efficiency, the photoactivities of all β-Bi 2 O 3 /Bi 2 S 3 heterostructures are continuously enhanced with growing test cycles, owing to the formation of Bi 2 O 3− x S x solid solution, in which the built-in electric filed induced by lattice distortion can brings about higher e − /h + separation efficiency. The gradually increasing photocatalytic activity can reach to an up limit in about 5 photocatalytic cycles and maintain at this level. β-Bi 2 O 3 /Bi 2 S 3 heterostructure loaded with 20 mol% of Bi 2 S 3 is demonstrated to be the best photocatalyst and capable of fully decomposing Rh B in 30 min. Our work provides deep insights into the nature of the inversed photocatalytic behavior and facilitates the advanced design of photocatalysts with unabated photoactivities.