Highly Responsivity of UV Photodetector Based on ZnO/PEDOT:PSS/CsCu2I3 Heterojunction

Perovskite materials have been widely developed for use in photodetectors due to their unique advantages, but most perovskites contain environmentally harmful lead. Herein, spin-coating is employed to fabricate nontoxic Cu-based perovskite films. By constructing a CsCu2I3 and ZnO heterojunction and incorporating a PEDOT:PSS hole transport layer, the ZnO/PEDOT:PSS/CsCu2I3 UV photodetector demonstrates a significantly enhanced spectral range and improved optoelectronic performance compared to a CsCu2I3 photodetector. Specifically, the photocurrent of ZnO/PEDOT:PSS/CsCu2I3 is enhanced by 3 orders of magnitude, reaching 1.43 × 10–4 A, and the responsivity is improved 57-fold to 0.67 A/W. This achievement provides an effective route for fabricating highly responsive Cu-based perovskite photodetectors.