Interface passivated quasi-2D perovskite-based highly stable photodetectors for weak-light detection

Weak-light detectors exhibiting long-term stability are of significant importance for both national defense and civilian applications. To address this, we fabricated a lateral high-performance photodetector (PD) based on a poly(N-vinylcarbazole) (PVK)-passivated 2D (PMA)2MAPb2I7 perovskite. The PVK passivation significantly improved both device performance and stability by suppressing vacancy formation and restricting grain boundary migration. The passivated PD achieved a nearly eightfold improvement in self-powered responsivity (R = 0.25 A·W−1, D* = 2.5 × 1011 Jones) and a sixfold enhancement under 5.0 V bias (R = 10.28 A·W−1, D* = 2.6 × 1012 Jones) in comparison with those of the pristine counterpart, showing a high performance compared to the other PDs based on perovskite materials. The passivated PD in self-powered mode demonstrated exceptional operational stability by maintaining 80.7% of its initial photocurrent over 1000 h in ambient air. Integrated into a custom optical communication system, this PD enabled reliable data transmission, while also delivering high-quality imaging under weak illumination (0.1 μW cm−2). This work provided a valuable design strategy for high-performance PDs, translating device innovations into practical solutions for self-powered, weak-light applications critical to emergency scenarios.