Controllable Crystal Growth and Improved Photocatalytic Activity of Porous Bi2O3-Bi2S3 Composite Sheets

Porous Bi2O3-Bi2S3 composite sheetswere constructed through a combinationalmethodologyof chemical bath deposition and hydrothermal reaction. The Na2S precursor concentration in the hydrothermal solution wasvaried to understand the correlation between the vulcanization degreeand structure evolution of the porous Bi2O3-Bi2S3 composite sheets. The control of the etchingrate of the Bi2O3 sheet template and the regrowthrate of Bi2S3 crystallites via suitable sulfideprecursor concentration during the hydrothermal reaction utilizesthe formation of porous Bi2O3-Bi2S3 sheets. Due to the presence of Bi2S3 crystallites and porous structure in the Bi2O3-Bi2S3 composites, theimproved visible-light absorption ability and separation efficiencyof photogenerated charge carriers are achieved. Furthermore, the as-synthesizedBi(2)O(3)-Bi2S3 compositesheets obtained from vulcanization with a 0.01M Na2S precursordisplay highly enhanced photocatalytic degradation toward methyl orange(MO) dyes compared with the pristine Bi2O3 andBi(2)S(3). The porous Bi2O3-Bi2S3 sheet system shows high surfaceactive sites, fast transfer, high-efficiency separation of photoinducedcharge carriers, and enhanced redox capacity concerning their constituentcounterparts. This study affords a promising approach to constructingBi(2)O(3)-based Z-scheme composites with a suitablemicrostructure and Bi2O3/Bi2S3 phase ratio for photoactive device applications.

Automated summary

Porous Bi2O3-Bi2S3 composite sheets were synthesized through a combination of chemical bath deposition and hydrothermal reaction, and the Na2S precursor concentration was varied to investigate the impact on the structure and vulcanization degree of the composites. The use of suitable sulfide precursor concentration during the hydrothermal reaction enabled the control of the etching rate of the Bi2O3 template and the regrowth rate of Bi2S3 crystallites, resulting in the formation of porous Bi2O3-Bi2S3 sheets. The presence of Bi2S3 crystallites and the porous structure in the composites contributed to improved visible-light absorption and separation efficiency of photogenerated charge carriers, making them highly promising for photoactive device applications.