Futuristic kusachiite solar cells of CuBi2O4 absorber and metal sulfide buffer layers: theoretical efficiency approaching 28 %

Abstract

Solar cells exhibit high performance using a thin semiconducting film with superior light harvesting ability. Though a variety of thin-film solar cells have shown promise, they suffer from long-term stability, strenuous processing, and high cost. This study evidence the capabilities of cheap and stable copper bismuth oxide or CuBi2O4 (CBO) as an efficient light absorber for thin-film photovoltaics. Solar Cell Capacitance Simulator-1D (SCAPS-1D) software is used to optimize the performance of CBO-based kusachiite solar cells with various n-type metal sulfide (MS) buffer layers (CdS, WS2, SnS2, and ZnS). The variation in the thickness of CBO light absorber and MSs buffer layers film had the highest control over power conversion efficiency (PCE) and other solar cell parameters. The effect of the work function of metal back contact and operating temperature on the performance of solar cells is also analyzed to assess the real-time application of the proposed metal sulfide and CBO based kusachiite solar cells. The highest efficiency of 27.73 % is observed for ITO/SnS2/CBO/Au solar cell device structure; however, the optimized solar cell device structure of ITO/WS2/CBO/Au showed a theoretical PCE of 22.84% in terms of thickness and doping density. CBO is synthesized by the hydrothermal route and characterized for phase purity, morphology, bandgap, and elemental composition through XRD, FESEM, UV Vis, and XPS techniques.