Here a combined DFT, SCAPS-1D, and wxAMPS frameworks are used to investigate the optimized designs of Cs2BiAgI6 lead-free double perovskite-based solar cells from ninety-six device structures using various electron and hole charge transport layers.

Lead-free Cs2BiAgI6 has garnered a lot of research interest recently due to its suitability as a potential absorber layer in the solar cell (SC) architecture owing to its low cost, good stability, and high efficiency. The main highlight of this research work includes the photovoltaic (PV) performance enhancement of Cs2BiAgI6 double perovskite solar cells (PSCs) by optimizing the optoelectronic parameters of the absorber, electron transport layer (ETL), hole transport layer (HTL), and various interface layers. Solar Cell Capacitance Simulator One dimension (SCAPS-1D) numerical simulation was used to optimize the performance of Cs2BiAgI6 absorber-based SCs consisting of copper barium thiostannate (CBTS) as the HTL and TiO2, PCBM, ZnO, IGZO, SnO2, and WS2 as ETLs. The role of the non-lead cesium-based halide perovskite absorber layer in the improvement of the SC performance was systematically investigated through a variation in the thickness, doping density, and defect density of the absorber layer, ETL, and HTL. The performance of the investigated device architectures is largely dependent on the thickness of the absorber layer, acceptor density, defect density, and the combination of different ETLs and HTLs. We found that TiO2, PCBM, ZnO, IGZO, SnO2, and WS2 ETL-based optimized devices recorded a power conversion efficiency (PCE) of 23.14, 23.71, 23.69, 22.97, 23.61, and 21.72%, respectively. Furthermore, the effect of series and shunt resistances, temperature, capacitance, and Mott–Schottky for the six optimized devices was estimated along with the computation of the corresponding generation and recombination rates, current density–voltage (J–V), and quantum efficiency (QE) characteristics. The PV parameters obtained from this comprehensive analysis are finally compared with the earlier published theoretical and experimental reports on Cs2BiAgI6 absorber-based SCs.

Since the conversion efficiency of silicon (Si)-based solar cells stagnates at 26.7% in the literature, extensive research and development activities are carried out on perovskite silicon-based tandem solar cells. However, the presence of lead (Pb) and the instability of perovskite prevent their large-scale implementation in the photovoltaic industry. Therefore, it is important to replace the hazardous material (Pb) in perovskite top cells to design non-toxic perovskite–silicon tandem solar cells. The current work yields much-needed studies to develop a non-toxic perovskite–silicon-based tandem solar cell. For the first time, methylammonium tin mixed halide (MASnI3–x Br x )-based materials are comprehensively investigated and optimized with respect to different halide compositions, absorber layer thickness, and bulk defect density in standalone configurations, followed by the development of a lead-free MASnI2Br1–Si-based tandem solar cell. The transfer matrix method and current matching techniques are used to design the two-terminal monolithic tandem cell, which showed a maximum conversion efficiency of 30.7% with an open circuit voltage (V OC) of 2.14 V. The results outlined in this manuscript will pave the way for the progress of highly efficient, non-toxic perovskite–silicon tandem solar cells.

With regard to perovskite solar cells (PSCs), a zinc oxide (ZnO) planar architecture has significant advantages from the upscaling perspective in terms of cost effectiveness and low-temperature processing compared to architectures with a mesoporous titanium dioxide (TiO 2 ) layer. Nevertheless, the perovskite (PVK) materials are unstable on a ZnO electron transport layer (ETL) during the annealing process. Herein, we discovered that the PVK material on top of the ETL changes to lead iodide (PbI 2 ) because of the presence of oxygen agents on the surface of ZnO. To tackle this issue, a hybrid photoelectrode of ZnO/graphene quantum dots (GQDs) is prepared and used as an ETL. As a result, green synthesized GQDs not only passivate the oxygen agents on the surface of the ZnO but also extract electrons rapidly from the PVK film to decrease the recombination of electron−hole pairs. Herein, findings reveal that PSC on ZnO:GQD ETL shows a power conversion efficiency (PCE) of up to 17% on fluorine tin oxide (FTO) under AM1.5G illumination. Consequently, the introduction of multifunctional GQD as an additive in ZnO ETL in PSCs displays a new and efficient tool in terms of environmental impact and economic feasibility for PSC commercialization.

In this study, we investigated the potential of CsPbI3 as an absorber material for use in perovskite solar cells (PSCs). To optimize the device, we used TiO2 as the electron...