Large-Scale 2D Perovskite Nanocrystals Photodetector Array via Ultrasonic Spray Synthesis

2D perovskite (PVSK) single crystals have received significant attention due to their unique optical and optoelectronic properties. However, current synthesis methods face limitations, particularly in large-area fabrication, which remain critical barriers to practical applications. In this study, the synthesis of red/green/purple-blue-colored 2D PVSK nanocrystals over a large area (4-inch wafer) and the fabrication of high-performance photodetector arrays are presented via a facile yet efficient spray-coating approach with a liquid-bridge transport effect. The photodetector array achieves 100% working yield, high photo-responsivity (1.5 × 10⁶ A W^-1) and specific-detectivity (1.1 × 10¹⁶ Jones) with competitive photomapping characteristics. An intelligent vision system for automatic shape recognition is further demonstrated with a recognition rate exceeding 90%. This study provides significant advances in the scalable synthesis of nanoscale 2D PVSK crystals, their integration into large-area optoelectronic devices, and their potential use in artificial-intelligence systems.