Single-channel UV/Vis dual-band detection with ZnCdS:Mn/ZnS core/shell quantum dots.

In an ultraviolet detection system, the Si-based photodetector could be sensitized with some kinds of fluorescent materials to enhance its response in the short-wavelength range. Thick-shell ZnCdS:Mn/ZnS core/shell quantum dots (QDs) exhibit unique advantage in UV signal sensitization due to their long PL lifetime, as well as stable emission matched with CCD's response. Herein, a single-channel UV panoramic detection system based on these Mn-doped QDs has been proposed. The QDs film was attached onto a Si-based CCD versus a tapered fiber, and an optical chopper was mounted before the QDs film. The long-lifetime fluorescence originating from UV signal could be still collected by the CCD when the chopper is in the "off" state, so the UV/Vis signal ratio is significantly enhanced.