Development and modeling of advanced systems Na <sub>2</sub> SnBr <sub>6</sub> -based perovskite solar cells: a comprehensive study on electron transport layers
Dipta Roy, Md. Selim Reza, Avijit Ghosh, Anup Roy, Bivash Ranjan Chowdhury, Md. Aktarujjaman, H.A. Alrafai, Abeer A. Hassan
Abstract
This study simulates a n-i-p planar heterojunction for Na 2 SnBr 6 -based perovskite solar cells (PSCs) , with Na 2 SnBr 6 as the absorber layer, fluorine-doped tin oxide (FTO) as the substrate, and In 2 S 3 , IGZO, and SnS 2 as electron transport layers (ETLs). Gold (Au) is used as the back contact. Na 2 SnBr 6 was chosen for its low cost, non-toxicity, tunable band gap, excellent electrical properties, and stability. The SCAPS-1D simulator was employed to model the solar cell performance under AM 1.5 G light irradiation, focusing on factors like doping concentration, layer thickness, defect density, and interface defects across three device configurations: Device I (Au/Na 2 SnBr 6 / In 2 S 3 /FTO/Al), Device II (Au/ Na 2 SnBr 6 /IGZO/FTO/Al), and Device III (Au/ Na 2 SnBr 6 /SnS 2 /FTO/Al). Device III achieved the highest PCE of 31.35%, FF of 85.95%, V OC of 0.7926 V, and J SC of 46.01 mA/cm 2 2 , making it a promising candidate for high-efficiency, lead-free perovskite solar cells. Devices I and II showed lower efficiencies of 27.47% and 30.98%, respectively. The study also analyzed quantum efficiency (QE), carrier dynamics, and recombination rates, highlighting the potential of Device III in advancing Na 2 SnBr 6 -based hybrid perovskite solar technologies for future solar energy applications.