Thin films of 2% Indium doped CdSe0.2Te0.8 were grown by thermal evaporation in a vacuum of 5 × 10-5 torr pressure on a precoated In2O3 coated glass plates. The thin films were characterized by X-ray diffraction (XRD) for structural determination, Optical absorption studies for band gap determination and an aqueous polysulphide comprising of (aq) 1M Na2S+ 1 M NaOH + 1M S was used as a redox electrolyte for fabrication of photoelectrochemical solar cells. The XRD pattern showed that the film exhibited a crystalline nature with zinc blende (cubic) structure with lattice constant a0= 4.22 Å. The optical absorption studies indicated that the semiconductor exhibits direct band gap with energy gap, Egγ 1.45 eV. The doping of 2% indium enhances the conductivity and thus the solar power conversion efficiency of φ= 1.6 % for the as grown thin films was obtained. The fill factor of 5% was obtained under AM 1.5 white light illumination with intensity of 100 mW/cm2. The quantum efficiency of the photo electro chemical solar cell was maximum for yellow (λγ570
