Suppressing Buried Interface Nonradiative Recombination Losses Toward High‐Efficiency Antimony Triselenide Solar Cells

Antimony triselenide (Sb₂ Se₃ ) has possessed excellent optoelectronic properties and has gained interest as a light-harvesting material for photovoltaic technology over the past several years. However, the severe interfacial and bulk recombination obviously contribute to significant carrier transport loss thus leading to the deterioration of power conversion efficiency (PCE). In this work, buried interface and heterojunction engineering are synergistically employed to regulate the film growth kinetic and optimize the band alignment. Through this approach, the orientation of the precursor films is successfully controlled, promoting the preferred orientational growth of the (hk1) of the Sb₂ Se₃ films. Besides, interfacial trap-assisted nonradiative recombination loss and heterojunction band alignment are successfully minimized and optimized. As a result, the champion device presents a PCE of 9.24% with short-circuit density (J_SC ) and fill factor (FF) of 29.47 mA cm^-2 and 63.65%, respectively, representing the highest efficiency in sputtered-derived Sb₂ Se₃ solar cells. This work provides an insightful prescription for fabricating high-quality Sb₂ Se₃ thin film and enhancing the performance of Sb₂ Se₃ solar cells.