Effect of PbS Film Thickness on the Performance of Colloidal Quantum Dot Solar Cells

Colloidal quantum dots offer broad tuning of semiconductor band structure via the quantum size effect. In this paper, we present a detailed investigation on the influence of the thickness of colloidal lead sulfide (PbS) nanocrystals (active layer) to the photovoltaic performance of colloidal quantum dot solar cells. The PbS nanocrystals (QDs) were synthesized in a non-coordinating solvent, 1-octadecene, using oleic acid (OA) as the ligand. It was found that the device with 50 nm of thickness of active layer showed a high Efficiency (η) of 0.667 under simulated Air Mass 1.5 Global (AM 1.5G) irradiation (100 mW/cm2) compared to the device with low thickness of active layer.