Modeling of ZrS₂/MoS₂ Heterostructures for Photovoltaic Applications

A single-junction heterostructure based on transition metal chalcogenides has been modeled using a solar cell capacitance simulator (SCAPS) to explore non-toxic materials for solar cell applications. The performance parameters of the proposed AZO/ZrS₂/MoS₂ heterojunction have been analyzed by varying the thickness of each layer and the doping concentrations. The impact of defect densities in ZrS₂ and MoS₂ on the performance parameters has been studied. The influence of metal back contact on the parameters has also been explored. The highest power conversion efficiency (PCE) of 14.13% has been obtained for thicknesses of 0.1 µm, 0.2 µm, and 3.0 µm of AZO, ZrS₂ , and MoS₂ layers, respectively. Other parameters obtained were the open circuit voltage (V_oc) = 0.5707 V, short circuit current density (J_sc) = 34.02 mA/cm³ , and fill factor (FF) = 71.35%. The external quantum efficiency (EQE) response and J–V characteristics of the optimized junctions are presented. The exponential grading law in SCAPS for the graded MoS₂ layer has been implemented to further enhance the PCE. Solar cell efficiency improved from 14.13% to 21.14% on the selenization of the MoS₂ absorber layer.