Minimization of carrier recombination in La2NiMnO6 double perovskite solar cells by optimizing defects and band offsets

Abstract

In the present work, an extensive study has been carried out on the parameters that govern the non-radiative recombination losses associated with the absorber double perovskite material. Four different device configurations have been proposed by incorporating different electron transport layers (ETL) namely tungsten disulfide (WS2), tungsten trioxide (WO3), zinc selenide (ZnSe), and strontium titanate (STO) with La2NiMnO6 (LNMO) double perovskite material as an active layer and cuprous oxide (Cu2O) as a hole transport layer (HTL). In this investigation, the role of band offsets in the collection, transportation, and recombination of charge carriers has been examined in detail. Further, the impact of thickness and the defect positions i.e. shallow defects and deep defects on the photovoltaic (PV) parameters of the cells has been thoroughly elucidated. The ideal barrier height between HTL and back contact (C, Ni, Ag, and Au) at various valence band maximum (VBM) levels has also been investigated for the proper collection of charge carriers. Interestingly, the results of the present simulation reveal that the WS2-based device with configuration FTO/WS2/LNMO/Cu2O/Au shows the highest PCE of 24.08% after optimization. The findings and interpretation of this work demonstrate that La2NiMnO6 an eco-friendly and non-toxic material can be used to produce high-efficiency perovskite devices.