Photodetector Based on Ag2Se Quantum Dots

With the emergence of new applications of infrared light detection technology, it is increasingly urgent to develop non-toxic and environmentally friendly alternative materials for heavy metal semiconductors. Ag₂Se quantum dots (QDs) has a relatively narrow band gap and is highly suitable for optical detection in the near-infrared to mid-infrared spectral region. Moreover, Ag₂Se QDs does not contain heavy metals and has a small impact on health and the environment. Due to the high electron mobility and wide spectral response characteristics of graphene and the high light absorption efficiency of QDs, the Ag₂Se QDs/graphene composite photodetector (PDs) has the advantages of high response and wide spectral detection range. In this paper, we designed and constructed PDs based on Ag₂Se QDs, and systematically studied the photoelectric detection performance. The photoelectric test of this device shows that under the irradiation of 808 nm light, Responsivity (R) is 342.24 A/W at a bias of 0.1 V, and Specific Detectivity (D*) is 3.35 × 10¹⁰ Jones. This work provides a reliable experimental idea for the preparation of high-performance infrared PDs.