Numerical simulations of 22% efficient all-perovskite tandem solar cell utilizing lead-free and low lead content halide perovskites
Rahul Pandey, Sakshi Sharma, Jaya Madan, Rajnish Sharma
Abstract
Abstract Lead-free or low lead content perovskite materials are explored in photovoltaic (PV) devices to mitigate the challenges of toxic lead-based halides. However, the conversion efficiency from such materials is far below compared to its counterparts. Therefore, to make a humble contribution in the development of lead-free or low lead content perovskite solar cells (PSCs) for future thin-film PV technology, a simulation study of tin (Sn) and Pb mixed halide (MAPb 0.5 Sn 0.5 I 3 , 1.22 eV) PSC is carried out in this manuscript. The device is further optimized in terms of transport layer and thickness variation to get 15.1% conversion efficiency. Moreover, the optimized narrow bandgap halide based device is further deployed in the monolithic tandem configuration with lead-free wide bandgap (1.82 eV) halide, i.e. Cs 2 AgBi 0.75 Sb 0.25 Br 6 , 1.82 eV (WBH) PSC, to mitigate the thermalization as well as transparent E g losses. Filtered spectrum, current matching, and construction of tandem J – V curve at the current matching point are utilized to design the tandem solar cell under consideration. Tandem device delivered short current density, J SC (15.21 mA cm −2 ), open-circuit voltage, V OC (1.95 V), fill factor, FF (74.09%) and power conversion efficiency, PCE (21.97%). The performance of the devices considered in this work is found to be in good approximation with experimental work.