Antisolvent-Free Metal Halide Perovskite Thin-Film Photodetectors

Developing a facile antisolvent-free method to prepare high-quality perovskite thin films is crucial for their applications in large-area image sensing. Herein, this work adopted methylammonium chloride (MACl) in the precursor to promote the nucleation and growth of FA _0.7 Cs _0.3 PbI ₃ perovskite thin films without using any antisolvent. It facilitated the formation of dense and uniform perovskite thin films with significantly increased light absorption and reduced trap states, thereby decreasing the contribution of trap-assisted tunnelling current to reverse-bias dark current density ( J_dark ) and suppressing the photogenerated carrier recombination loss. As a result, the perovskite photodetector array exhibited excellent photodetection performance and good device uniformity, including high peak photoresponsivity of 0.35 A/W, low J_dark of 4.3×10 ^-9 A/cm ² at -0.1 V, high specific detectivity of 1.0 × 10 ¹² Jones, and fast response/recovery of 0.97/6.63 μs.