阳离子交换法可控制备 CdS@PbS 核壳量子点及其近红外探测器性能

The CdS quantum dots(QDs)were converted into CdS@PbS core-shell QDs with near-infrared(NIR)absorption capacity by cation exchange strategy in N, N-dimethylformamide(DMF)solvent. We characterized the morphology, elemental composition, crystal structure and optical properties of CdS@PbS core-shell QDs by transmission electron microscopy(TEM), X-ray powder diffraction(XRD)and UV-Vis-NIR spectrophotometer. Considering their unique NIR absorption properties, these CdS@PbS core-shell QDs were specially utilized for fabricating self-powered photoelectrochemical-type NIR photodetector(PD). The PDs exhibit an excellent photoresponse performance under 850 nm illumination, with a typical on/off ratio of 2277, a responsivity of 83. 3 mA/W, and a detectivity of 2. 91×10¹¹ Jones. Notably, the PD shows a good linear relationship between the photocurrent and the incident light intensity, indicating that the device can achieve stable detection under 850 nm illumination with different light intensities.