Ultrawide Bandgap Organic–Inorganic Hybrid Perovskite [C 6 N 2 H 18 ][CdCl 4 ] for Solar-Blind Ultraviolet Detection

Solar-blind ultraviolet (UV) detection is a core technology for applications such as environmental monitoring, flame detection, and remote early warning response. So far, there are still very few inorganic-organic hybrid perovskites (OIHPs) with the characteristic of the absorption edge in the solar-blind UV region. Herein, we present a high-performance solar-blind UV photodetector based on a two-dimensional (2D) OIHPs [C₆N₂H₁₈][CdCl₄], which exhibits a direct bandgap of 5.13 eV and an exceptional carrier lifetime of 504 μs. The device demonstrates a remarkable photocurrent of 152.1 nA/cm² and a rapid response time of 35 μs under 254 nm UV illumination. Compared to traditional inorganic detectors (e.g., Ga₂O₃, AlGaN), this hybrid material offers structural flexibility and low-temperature solution processability, addressing the trade-offs between sensitivity and mechanical robustness. Our work pioneers the use of ultrawide bandgap OIHPs for solar-blind UV sensing, providing a viable alternative to rigid inorganic semiconductors.