Comment on "Improving the efficiency of a CIGS solar cell to above 31% with Sb₂S₃ as a new BSF: a numerical simulation approach by SCAPS-1D" by M. F. Rahman and S. Goumri-Said et al., RSC Adv., 2024, 14, 1924

It was reported in early 2024 that a single-junction 1.1 eV bandgap copper indium gallium selenide (CIGS) solar cell can achieve actual power conversion efficiency up to 40.70%, open circuit voltage up to 1.330 V, and fill factor up to 90.55% at 300 K when the solar cell is irradiated by the air mass 1.5 global (AM1.5G) solar spectrum (M. F. Rahman et al., RSC Adv., 2024, 14, 1924-1938). These simulated solar cell performance parameters exceed the ideal detailed balance-limiting power conversion efficiency, open circuit voltage, and fill factor of a 1.1 eV bandgap single-junction solar cell.