Physical properties and photoresponse of Cu–Ag–In–S semiconductor electrodes created using chemical bath deposition

Cu–Ag–In–S solid solution semiconductor films were grown on indium–tin oxide-coated glass substrates using chemical bath deposition. New procedures for the growth of Cu–Ag–In–S semiconductor films are presented. The optical, electrical, and photoelectrochemical performances of the ternary CuInS2, AgIn5S8, and their solid solutions are investigated. The X-ray diffraction patterns of samples reveal a change in the crystal phase of the samples from the tetragonal CuInS2 to the cubic AgIn5S8 phase with an increase in the [Ag/(Cu+Ag)] molar ratio in precursor solutions. The thicknesses and band gaps of the samples, determined from the surface profile measurements and transmittance spectra, are in the ranges of 841–2107 nm and 1.42–1.75 eV, respectively. The highest photoresponse was observed in the sample with [Ag/(Ag+Cu)]=0.4 (sample (d)) under illumination with a white light intensity of 100 mW/cm2. The results show that Cu–Ag–In–S film electrodes have potential in solar to hydrogen applications.