Experimental optimization of molar concentration to fabricate PbS quantum dots for solar cell applications

Lead sulfide (PbS) quantum dots were prepared by successive ion layer adsorption and reaction technique based on spin-coating (spin-SILAR). The effect of molar concentration of solution on optical and photovoltaic properties was studied.Optimized PbS quantum dot sensitized solar cell demonstrated maximum power conversion efficiency of 3.29% with short-circuit current of 10.06 mA/cm2 and open-circuit voltage of 0.59 V under 1 sun illumination (AM1.5). The results showed that PbS QD layer fabricated by a solution with molar concentration of 5 mM can be used as a highly efficient sensitizer for solar cells. PbS QD layer acts as light absorber and recombination blocking layer in the ITO/ZnO film/PbS QD/P3HT/PCBM/Ag structure.