Cd2+ doped PbS thin films for photovoltaic applications: Novel low-cost perspective

In the present study, we have investigated the effect of Cd2+ nominal content (x(solution) = [Cd2+]/[Pb2+] = 0.5 at%, 1 at%, 1.5 at% and 2 at%) on PbS thin films grown on ordinary glass substrates using the chemical bath deposition (CBD) technique. The effect of Cd2+ content on structural, morphological, optical and electrical properties of PbS thin films was studied. X-ray diffraction (XRD) and scanning electron microscopy (SEM) showed that Cd2+ doped PbS thin films have good polycrystalline nature with cubic structure. It was found that the chemical bath deposition made (x(solution) = 1 at%) Cd2+ doped PbS has an excellent optical and electrical characteristics, which shows its applicability in p-n junction solar cells in combination with indium oxide (In2O3) thin films. Being illuminated under 100 mW/cm(2) sunlight, from the current-voltage characteristic of the FTO/In2O3(n)/Cd:PbS(p)/Al device the photovoltaic parameters were extracted: Open circuit voltage (V-oc=635 mV), short circuit current density (J(sc) = 12.36 mA/cm(2)), fill factor (FF=0.32), and conversion efficiency (eta = 2.5%).