Enhanced Performance of Sn-Based Perovskite Photodetectors Through Double-Sided Passivation for Near-Infrared Applications

The development of high-performance Sn-based perovskite photodetectors is presented with double-sided passivation using large alkylammonium interlayers of PEAI and BDAI(2). This dual passivation strategy, applied to the top and bottom of FASnI(3) films, effectively improves film quality by reducing defect density, enhancing carrier mobility, and minimizing non-radiative energy losses at the interfaces. At 720 nm, the photodetectors demonstrate a responsivity of 0.37 A W-1, a detectivity of 6.12 x 10(1)3 Jones, and an external quantum efficiency (EQE) of 65.60%, with a rapid response time of 9 mu s. Additionally, at 850 nm, the detectivity reaches as high as 3.27 x 10(1)3 Jones. Furthermore, the device demonstrated a low 1/f noise of 1.21 x 10(-1) AHz(-). at 10 Hz. Transient photocurrent (TPC) and transient photovoltage (TPV) measurements revealed a significant increase in charge recombination lifetime (tau e) and improved charge transfer efficiency. These results showcase the potential of Sn perovskite photodetectors for near-infrared applications, including autonomous vehicles, biometric recognition, and biomedical treatments.