Electrochemical-based studies of Cu2SnSe3 nanocrystals and P3HT:PCBM for hybrid solar cells

In this work, we have fabricated hybrid heterojunction solar cells with structure ITO/ZnO/P3HT:PCBM:CTSe NCs (optimized weight percentage 10 wt%)/MoO3/Ag (device SM10). A thin layer of molybdenum oxide MoO3 prepared by peroxomolybdic acid organosol as the precursor was used as hole transport layers (HTLs). The performance of the device was compared with ITO/ZnO/P3HT:PCBM:CTSe NCs/Ag(device S10). The important parameters such as global charge carrier mobility (µ), effective charge carriers lifetime (τn) and charge diffusion time (τd) have been extracted from electrochemical impedance spectroscopy (EIS) performed at the bias of 0.1 V in the dark. The Nyquist plot obtained from EIS has demonstrated effective carriers lifetime, global mobility and charge diffusion time for a device SM10 as 6.46 ms, 12.6 × 10−4 cm2 V−1 S−1 and 5.2 µs and for device S10 as 5.65 ms, 9.58 × 10−4 cm2 V−1 S−1 and 6.8 µs, respectively.