Short-Wave Infrared Focal Plane Arrays Enabled by Reactivity-Engineered PbSe Quantum Dots

PbSe colloidal quantum dots (CQDs) are promising materials for short-wave infrared (SWIR) imaging, owing to their suitable bandgap, low-cost fabrication, and solution processability. Nevertheless, achieving precise size control together with large size uniformity across a broad infrared spectral range remains a significant challenge, which has consequently limited the development of high-performance PbSe CQD-based infrared photodetectors and imaging systems. In this work, we report a reactivity-engineered synthesis strategy that enables chemical decoupling of nucleation and growth by rationally designing selenium precursors with distinct reactivities. This approach enables the synthesis of size-tunable PbSe CQDs with exceptional size uniformity, yielding particle diameters from 3.26 to 10.14 nm with size deviations below 5%. Leveraging these high-quality materials, we fabricate, for the first time, monolithic PbSe CQD imaging arrays with a resolution of 640 × 512 pixels operating in the extended SWIR region. The resulting imager exhibits a high detectivity of 1.2 × 10¹¹ Jones at approximately 2000 nm and delivers robust imaging performance at room temperature. These results establish an effective strategy for the synthesis of high-quality PbSe CQDs and highlight their strong potential for high-performance, room-temperature SWIR imaging applications.