Facile fabrication of porous thin films of Bi2O3/Bi2S3 nanocomposite semiconductors at gas/liquid interface and their photoelectrochemical performances

•Porous films of Bi2O3/Bi2S3 were obtained at gas/liquid interface in a short time.•By contacting acidic Bi(NO3)3 solution with vapors from NH3 and (NH4)2S solutions.•Hydrolysis, sulfurization and self-assembly occurred at/near the acidic solution surface.•Adjusted film thickness/composition by concentration, vapor source and contact time.•The photocurrent density on the prepared Bi2O3/Bi2S3 films reached to 1.8 mA cm−2.

Porous thin films of Bi2O3/Bi2S3 nanocomposite semiconductors were prepared rapidly at gas/liquid interface for the first time by contacting an acidic Bi(NO3)3 solution with vapors from ammonia water and ammonium sulfide solution. Hydrolysis of Bi3+ into Bi2O3 nanoparticles (NPs) and their partial sulfurization into Bi2S3 occurred at/near the solution surface upon contacting the vapors of NH3 and H2S, respectively. Based on photoelectrochemical performances, the conditions were optimized for preparation of Bi2O3/Bi2S3 thin films by interfacial reactions and self-assembly of the in situ produced nanocomposites, including concentrations of Bi(NO3)3 and HNO3, vapor sources, contact manners and contact times. The porous thin film of Bi2O3/Bi2S3 prepared under optimized conditions showed better photoelectrochemical performance than the respective thin films of Bi2O3 and Bi2S3 and their some other composites.

Graphical abstractPorous thin films of Bi2O3/Bi2S3 nanocomposites were prepared rapidly at gas/liquid interface with high photoelectrochemical performances.Download full-size image