The enhanced photovoltaic performance of perovskite solar cell using carbon nanotubes as hole transport material

Abstract

Perovskite based solar cells have enjoyed rapid and an unprecedented evolution over the past decade. These light-harvesting materials are of huge interest to the academic community in order to make more efficient solar cells which are expected to attain swift commercialization. They have attractive properties, most especially their high-power conversion efficiency (PCE) within few years in comparison to other third generation thin film technologies. In This research work, the effect of incorporating multi-walled carbon nanotubes as the hole-transport layer on the photovoltaic performance of perovskite solar cells was investigated. UV-Vis spectrophotometry, Scanning Electron Microscopy, Surface Profilometer, Raman Spectroscopy and Solar Simulator were used to characterize and study the properties of the prepared cells. The reference cell demonstrated a PCE, current density (Jsc), open circuit voltage (Voc) and fill factor (FF) of 2.82 %, 7.64 mAcm-2, 0.88 V, and 42.00 % respectively. When multi walled carbon nanotubes (MWCNTs) was incorporated, we observed a PCE of 4.30 %, Jsc of 8.47 mAcm-2, Voc of 0.85 V and FF of 60.00 %. The MWCNTs modified device shows an enhancement of 52.48 % in PCE, 10.86 % in Jsc, and 42.86 % in FF over the unmodified device. This is due to improved surface area of MWCNTs by acid treatment in generating functional groups that act as conducting bridge in reducing the contact resistance between individual nanotubes.