Abstract
Antimony selenosulfide, denoted as Sb(2)(S,Se)(3), has garnered attention as an eco-friendly semiconductor candidate for thin-film photovoltaics due to its light-absorbing properties. The power conversion efficiency (PCE) of Sb(2)(S,Se)(3) solar cells has recently increased to 10.75%, but significant challenges persist, particularly in the areas of open-circuit voltage (V(oc)) losses and fill factor (FF) losses. This study delves into the theoretical relationship between V(oc) and FF, revealing that, under conditions of low V(oc) and FF, internal resistance has a more pronounced effect on FF compared to non-radiative recombination. To address V(oc) and FF losses effectively, a phased optimization strategy was devised and implemented, paving the way for Sb(2)(S,Se)(3) solar cells with PCEs exceeding 20%. By optimizing internal resistance, the FF loss was reduced from 10.79% to 2.80%, increasing the PCE to 12.57%. Subsequently, modifying the band level at the interface resulted in an 18.75% increase in V(oc), pushing the PCE above 15%. Furthermore, minimizing interface recombination reduced V(oc) loss to 0.45 V and FF loss to 0.96%, enabling the PCE to surpass 20%. Finally, by augmenting the absorber layer thickness to 600 nm, we fully utilized the light absorption potential of Sb(2)(S,Se)(3), achieving an unprecedented PCE of 26.77%. This study pinpoints the key factors affecting V(oc) and FF losses in Sb(2)(S,Se)(3) solar cells and outlines an optimization pathway that markedly improves device efficiency, providing a valuable reference for further development of high-performance photovoltaic applications.