Scrutinizing the untapped potential of emerging ABSe3 (A = Ca, Ba; B = Zr, Hf) chalcogenide perovskites solar cells

Abstract ABS 3 chalcogenide perovskites (CPs) are emerging as promising alternatives to lead halide perovskites due to their unique properties. However, their bandgap exceeds the Shockley-Queisser limit. By substituting S with Se, the bandgap is significantly reduced, shifting it from the visible into the near-infrared region. Hence, we have investigated the potential of Se-based absorbers with device structure FTO/TiO 2 /ABSe 3 (A = Ca, Ba; B = Zr, Hf)/NiO/Au using SCAPS-1D. We analyzed the critical parameters impacting each layer of the solar cell. Notably, we achieved an enhanced light absorption (~ 26.5%) at an optimal absorber thickness (500 nm), intensifying carrier generation. Additionally, we observed an increase in V OC (1.03 V) due to improved quasi-Fermi level splitting and a reduction in energy loss (0.45 V) across all solar cells with an optimal absorber carrier concentration (10 16 cm −3 ). Overall, the optimization resulted in improvements in PCE by the difference of 20.14%, 20.44%, 14.33%, and 14.56% for CaZrSe 3 , BaZrSe 3 , CaHfSe 3 , and BaHfSe 3 solar cells, respectively. The maximum PCE of over 30% was attained for both CaZrSe 3 and BaZrSe 3 solar cells, attributed to their narrow bandgap, enhanced light absorption (53.60%), high J SC (29 mA/cm 2 ), and elevated generation rate of 1.19 × 10 22 cm −2 s −1 . Thus, these significant outcomes highlight the potential of these absorbers for fabricating high-efficiency CP solar cells.