Photodetection Performance of Sb 3+ Doped Cd 0.92 Hg 0.08 S Based Electrochemical Cells

The present investigation deals with the preparation of Sb3+ doped (from 0.01 to 1 mol%) Cd0.92Hg0.08S thin films onto the well polished and cleaned stainless steel substrates. The previously optimized conditions were used for the deposition. The electrochemical photosensing cells were fabricated out of these series of Sb3+ doped Cd0.92Hg0.08S photoactive electrodes and sulphide/polysulphide (0.2 M) as an electrolyte. The cells were then characterized through the various properties and their performance has been studied with a special reference to the Sb3+ doping concentration. The cells were illuminated with a white light of (13 mW/cm3) intensity and the cell parameters such as photocurrent (Iph), photo voltage (Vph), the electrochemical conversion efficiency (η), fill factor (ff) etc., have been determined. It is found that Iph, Vph, η% and ff% have been boosted significantly with Sb3+ doping concentration up to 0.1 mol% and then decreased. Typically, Iph enhanced from 0.152 to 0.214 mA/cm2 and that Vph from 297 to 391 mV whereas η increased from 1.27 to 2.41% and ff from 36.44 to 38.65%. The junction ideality factors were determined and indicated that the recombination mechanism is dominant at the electrode/electrolyte interface. The capacitance—voltage measurements showed Vfb to be enhanced from −1.068 to −1.297 V (Vs SCE). Barrier potential measurements determined Pool—Frenkel type conduction mechanism. Overall the photovoltaic detector performance has been found to be boosted significantly at 0.1 mol% Sb3+ doping concentration in Cd0.92Hg0.08S electrode.