A high-performance solution-processed near-infrared phototransistor with a non-toxic Ag₂Te colloidal quantum dots/ZnO heterostructure channel

The development of high-performance, solution-processed near-infrared (NIR) photodetectors remains a challenge, particularly those that are non-toxic and exhibit a broad spectral response. In this work, a high-performance NIR photodetector based on a solution-processed field-effect transistor is demonstrated utilizing a non-toxic colloidal quantum dot (CQD) heterostructure channel. Uniformly sized and well-dispersed Ag₂Te CQDs are synthesized to form a ZnO/Ag₂Te heterostructure for efficient NIR light absorption. The realized photodetector presents a record-high responsivity of 1.52 × 10³ A W⁻¹ and detectivity of 2.1 × 10¹¹ Jones, along with a low response time of 19.06 ms under low-intensity 940 nm light illumination. Moreover, the device maintains high responsivity and detectivity under 895 nm and 1000 nm NIR illumination, exceeding 300 A W⁻¹ and 5 × 10¹⁰ Jones, respectively. This work demonstrates a novel approach to fabricating high-performance, non-toxic NIR active matrix sensing arrays for in vivo imaging and biosensing.