Regulating deposition kinetics via a novel additive-assisted chemical bath deposition technology enables fabrication of 10.57%-efficiency Sb2Se3 solar cells

Abstract

Synthesizing high-quality films with superior morphological, electrical, and defect properties is the basic requirement for obtaining high-efficiency solar cells. Recently, Sb₂Se₃ has been the emerging photovoltaic material with a low-symmetry crystal structure and complicated defect properties, giving a unique synthesis challenge for high-performance solar devices. In this work, we developed a novel additive-assisted chemical bath deposition (CBD) technology for producing ideal antimony triselenide (Sb₂Se₃) films using antimony potassium tartrate and sodium selenosulfate as antimony and selenide sources, respectively, with thiourea and selenourea as additives to manipulate the deposition process. We uncover that additive regulated deposition kinetics is essential to improve the film properties. Comprehensively, the physical properties of Sb₂Se₃ films in terms of morphology, crystallinity, carrier transport properties, and defect density have been significantly enhanced. As a result, we achieved a power conversion efficiency of 10.57% in Sb₂Se₃ solar cells, which represents the highest efficiency of Sb₂Se₃ solar cells, regardless of the fabrication methods and device structures. Given the scalability to large area production and the low-cost fabrication characteristics of the CBD technique, this study demonstrates not only an effective and implementable method for fabricating highly efficient Sb₂Se₃ solar cells but also paves the way for industrial production of large-area Sb₂Se₃ photovoltaic panels in the future.