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

ABSTRACT

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 × 10 ¹¹ 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.