Fullerene for the Improvement of PbS QDs-Based Hybrid Solar Cells

Abstract

In the present study, the hybrid photovoltaic devices based on PbS quantum dots (QDs) and poly(3-hexylthiophene-2,5diyl) have been fabricated. The effect of the insertion of [6,6]-phenyl C₇₁ butyric acid methyl ester (PCBM) into the hybrid blend has been investigated and analyzed by using light and dark current density-voltage measurement, and impedance spectroscopy: capacitance-frequency and capacitance-voltage measurement. It is demonstrated that the introduction of PCBM into solar cells improves their efficiency with the optimal PCBM concentration of 3 wt %. It is shown that the main contribution in limitation of solar cells efficiency is brought by shallow traps induced by air exposure.