Simulating the performance of a high-efficiency SnS-based dual-heterojunction thin film solar cell

This article demonstrates a novel high efficiency ZnS/SnS/MoS₂ dual-heterojunction thin film solar cell. The device has been optimized with respect to the thickness, doping concentration, and defect density of each constituent layer including working temperature and back contact metal work function using SCAPS-1D simulator. The MoS₂ plays a promising role to serve as a back surface field (BSF) layer with commendatory band alignment, which provides an opportunity for higher absorption of longer wavelength photons utilizing the tail-states-assisted (TSA) two-step photon upconversion approach. The insertion of MoS₂ in the ZnS/SnS pristine structure offers a significant improvement of the power conversion efficiency (PCE) within the detailed-balance limit with a rise from 20.1 to 41.4% with V_OC of 0.91 V, J_SC of 53.4 mA/cm² and FF of 84.9%, respectively. This result reveals MoS₂ as an effective BSF for low cost, highly efficient dual-heterojunction structure for future fabrication.