Effect of Sb on the growth and photoelectrochemical response of AgIn5S8 film electrodes created by solution growth technique

Sb-doped AgIn5S8 polycrystalline films were grown on indium–tin–oxide coated glass substrates using solution growth technique. New procedures for growing Sb-doped Ag–In–S system photocatalyst films are presented. The influences of various deposition parameters on structural, optical, and photoelectrochemical properties of samples were investigated. The X-ray diffraction patterns of samples demonstrate the presence of polycrystalline AgIn5S8 phase in these films. The thicknesses and energy band gaps obtained from transmittance data are in the ranges of 538–1018 nm and 1.72–1.73 eV, respectively. The flat band potentials of these samples are in the range of −4.097 to −5.217 V vs. an absolute electron potential; the potentials become more negative with an increase in Sb ion in reaction solution. With a molar ratio of Sb/Ag in precursor solution higher than 0.2, the conduction type of samples turns into p-type semiconductor. The maximum photocurrent density of samples with an external potential set at 3.5 V was found to be −4.76 mA/cm2 under illumination using a 300 Xe lamp system.