Theoretical insights into a high-efficiency Sb₂Se₃-based dual-heterojunction solar cell

Here, we manifest the design and simulation of an n-ZnSe/p-Sb₂Se₃/p -AgInTe₂ dual-heterojunction (DH) solar cell which exhibits a prominent efficiency. The performance of the solar cell has been assessed with reported experimental parameters using SCAPS-1D simulator by varying thickness, doping concentration and defect density in each layer. The proposed structure shows an efficiency of 38.6% with V = 0.860 V, J = 54.3 mA/cm² and FF = 82.77%, respectively. Such a high efficiency close to Shockley-Queisser (SQ) limit of DH solar cell has been achieved as a result of the longer wavelength photon absorption in the p -AgInTe₂ back surface field (BSF) layer through a tail-states assisted (TSA) two-step photon upconversion phenomenon. These results indicate hopeful application of AgInTe₂ as a bottom layer in Sb₂Se₃-based solar cell to enhance the cell performance in future.