Lead‐Free Perovskite Photodetector With Broad Spectral Response Enabled by Cz‐Pyr‐Based Hole Transport Layer

Perovskite photodetectors have attracted significant attention due to their unique properties in optoelectronic applications. Lead‐based perovskite photodetectors are particularly known for their high current density; however, their large‐scale commercialization is limited by the toxicity of lead‐based absorbers. Consequently, research efforts are increasingly focused on developing lead‐free alternatives. In this context, silicon and germanium (Sn and Ge), belonging to Group 14 elements, are proposed as potential replacements for lead (Pb). The effects of defect density, doping concentration, photoactive layer thickness, parasitic resistance, operating temperature, and interface defect density on device performance have been systematically investigated. The results demonstrate that the FTO/GO/CsSn 0.5 Ge 0.5 I 3 /Cz‐Pyr/C configuration achieves a short‐circuit current density ( J sc ) of 28.50 mA/cm 2 , detectivity ( D *) of 1.1 × 10 14 Jones, and responsivity ( R ) of 0.66 A/W, representing a significant improvement over previous studies. This simulation study provides valuable insights for the development of cost‐effective and high‐performance perovskite photodetectors (PePd), contributing to advancements in optoelectronic technology.