Lead Halide Perovskite Solar Cells have exhibited the highest efficiencies for Perovskite Solar Cells. As a result of its affordable processing costs, and stability, HTL-free PSCs have grown in popularity in recent years. A comprehensive numerical study of a novel HTL-free PSC, with a structure of FTO/ZnO/WS₂/CH₃NH₃PbI₃/Au, is reported in this article. Multiple factors that affect the performance of the solar cell have been thoroughly investigated like absorber thickness, doping density and deep level defect density. Also, the influence of the interface defects has been closely studied. Finally, the impact of a gradient doping concentration on the performance parameters has been analyzed. After optimization, we have obtained the final simulated device parameters of power conversion efficiency(PCE) of 26.25%, with an open-circuit voltage(Voc) of 1.20 V, a short-circuit current(Jsc) of 24.60 mA/cm2, and a Fill Factor(FF) of 89.04%, which is an improvement on the best values recorded in literature.