Design and efficiency improvement of eco-conscious Sr3PBr3 and Sr3NCl3 double perovskite solar cells with IGZO and Cu2O as ETL and HTL

• A research project was initiated to evaluate how efficient solar cells are by investigating the effect of double perovskite solar cells with IGZO and Cu 2 O as ETL and HTL in the designs of Al/FTO/IGZO/Sr 3 PBr 3 /Sr 3 NCl 3 /Au, and Al/FTO/IGZO/Sr 3 PBr 3 /Sr 3 NCl 3 /Cu 2 O/Au. • The absorber and ETL layers received upgrades, which included changes to thickness, acceptor density, donor density, absorption coefficient, series shunt resistance, and defect density. • This work achieved a peak PCE of 30.34 and 32.46 %, with J SC of 26.45 and 26.51 mA/cm 2 , FF of 90.14 and 87.26 %, and V OC of 1.27 and 1.40 V without and with HTL. • This setup brings important benefits for assessing future progress in solar cell technology. This research presents a new design for double perovskite solar cells (DPSCs) utilizing Sr 3 PBr 3 and Sr 3 NCl 3 , which is noted for its enhanced stability in comparison to conventional single perovskite materials, thereby making it ideal for the development of ultra-thin, very efficient solar cells. The proposed architecture features a distinctive arrangement: Al/FTO/IGZO/Sr 3 PBr 3 /Sr 3 NCl 3 /Cu 2 O/Au. The study provides an in-depth theoretical examination of the energy band structure, defect properties, and quantum efficiency of the DPSC, focusing on the optimized photovoltaic (PV) specifications. Remarkably, the optimized DPSC achieves a power conversion efficiency (PCE), an open-circuit voltage ( V OC ), a short-circuit current density ( J SC ), and a fill factor (FF) of 32.46 %, 1.40 V, 26.51 mA/cm 2 , 87.26 %. Whereas without HTL, the PV parameters are PCE of 30.34 %, V OC of 1.27 V, J SC of 26.45 mA/cm 2 , and FF of 90.14 %. The impressive efficiency of 32.46 % is due to better charge extraction, improved alignment between the absorber and transport layers, and reduced losses from recombination. The double perovskite absorber's special characteristics, along with accurate doping and defect technology, allow for effective charge transfer and collection. Additionally, the research explores the influence of various factors such as temperature, interface defects, rates of carrier production and recombination, and the work functions of return contact materials on performance. The results underscore the significant potential of Sr 3 PBr 3 and Sr 3 NCl 3 , especially when combined with the Cu 2 O HTL, in effectively reducing sheet resistance and enhancing overall solar cell efficiency. Validation of the design was performed using SCAPS-1D simulation software.