Highly stable CdTe quantum dots hosted in gypsum via a flocculation-precipitation method

Poor stability hinders the practical application of aqueous CdTe quantum dots (QDs) in optoelectronic devices. In this work, a flocculation-precipitation method is demonstrated to host aqueous CdTe QDs in gypsum to form CdTe-gypsum nanocomposites, which is simple, effective and environmental-friendly. Ascribed to gypsum acting as a tight and robust matrix protection agent, the photo-, thermal-, anti-acid and long-term stability of CdTe QDs were remarkably improved. Moreover, this approach solved the problem of incompatibility between aqueous QDs and epoxy resin, allowing for the application of aqueous QDs in white light emitting diodes (WLEDs), based on which a WLED with the red-emission nanocomposites used as a color-conversion layer was successfully fabricated. These results indicate the potential of this technique in stabilizing aqueous QDs as well as their practical application in optoelectronic devices.