PHOTOELECTROCHEMICAL BEHAVIOR OF ZN3IN2S6 SINGLE-CRYSTALS IN AQUEOUS-SOLUTIONS

The basic photoelectrochemical behaviour and some physical quantities of the ternary semiconductor n-Zn3In2S6 have been investigated for the first time. From the photocurrent actions spectrum in 1M Na2SO4 a direct optical band gap energy (Eg) equal to 2.81 eV has been determined. From capacity measurements a flat band potential (VFB 0 - 1.29 V SCE) has been calculated, as well as the donor density, the conduction and the valence band edge. With pH increasing, a shift of the photocurrent onset potential (Von) to more cathodic values has been observed. The presence of redox systems such as Na2S/NaOH, Na2SO3, K3[Fe(CN)6]/ K4[Fe(CN)6], Ce3+/Ce4+ improves the stability of the electrodes and produces reasonable photovoltages. © 1990.