A comparative photo-electrochemical study of compact In2O3/In2S3 multilayer thin films

Indium sulfide (In2S3) thin films have been successfully deposited by chemical bath deposition (CBD) onto indium-doped-tin-oxide (ITO) substrates from an aqueous mixture containing indium chloride and thioacetamide at 343 K. As-deposited films were annealed at 673 K to convert into In2O3, as confirmed by the measurement of energy dispersive X-ray analysis (EDAX). Over In2O3, again In2S3 film was deposited using CBD to form In2O3/In2S3 bilayer, where In2O3 served as an effective window and/or hole blocking layer and In2S3 as a sensitizing layer. Enhanced photochemistry was confirmed from photo-electrochemical (PEC) measurement, where multilayer thin films showed better performance with solar conversion efficiency (η%) of 0.17% than In2O3 and In2S3.