Room-Temperature\nDirect Synthesis of PbSe Quantum\nDot Inks for High-Detectivity Near-Infrared Photodetectors

Abstract

A PbSe\ncolloidal quantum dot (QD) is typically a solution-processed\nsemiconductor for near-infrared (NIR) optoelectronic applications.\nHowever, the wide application of PbSe QDs has been restricted due\nto their instability, which requires tedious synthesis and complicated\ntreatments before being applied in devices. Here, we demonstrate efficient\nNIR photodetectors based on the room-temperature, direct synthesis\nof semiconducting PbSe QD inks. The in-situ passivation and the avoidance\nof ligand exchange endow PbSe QD photodetectors with high efficiency\nand low cost. By further constructing the PbSe QDs/ZnO heterostructure,\nthe photodetectors exhibit the NIR responsivity up to 970 mA/W and\na detectivity of 1.86 × 10¹¹ Jones at 808 nm. The\nobtained performance is comparable to that of the state-of-the-art\nPbSe QD photodetectors using a complex ligand exchange strategy. Our\nwork may pave a new way for fabricating efficient and low-cost colloidal\nQD photodetectors.