Effect of a Metal–Semiconductor Hetero Nanostructure of Cu/Bi2Se3 on Optical Properties of Perovskite Solar Cells

An up to 25% power conversion efficiency and performance improvement of perovskite solar cells (PSCs) have made them promising products in photovoltaic technology. This study numerically investigates the light trapping and broadband light absorption enhancement of a PSC by introducing bismuth selenide (Bi2Se3) as shell material for Cu nanospheres (NSs) to achieve a “core/shell” configuration (Cu/Bi2Se3NSs) in the absorber layer of the PSC. The optimal values of Cu NS radius, Bi2Se3 thickness, periodicity of NSs, and the thickness of the absorber layer of PSC are equal to 40, 35, 172.5, and 410 nm, respectively. This structure has a photocurrent density (JL) of 33.01 mA cm−2 and a maximum normalized absorbed power (Pabs_total) of 0.89 compared to the bare PSC with JL = 21.8 mA cm−2 and Pabs_total = 0.87. The results indicate that the increase in the Bi2Se3 thickness up to 35 nm at a fixed Cu NS radius of 40 nm can enhance the absorption in the whole spectrum. However, this enhancement is greater at longer wavelengths. The extinction cross‐section is improved by about 3.5 times in comparison with the bare Cu NSs. The results for the PSC with Cu/Bi2Se3 NSs show a 51.3% absorption enhancement compared to the PSC without NSs. This study numerically investigates the light trapping, broadband light absorption enhancement at longer wavelengths, and increasing of photocurrent density of the perovskite solar cell (PSC) by introducing a metal–semiconductor hetero nanostructure of Cu/Bi2Se3 with “core/shell” configuration compared to the PSC without plasmonic nanosphere.