One-pot, large-scale synthesis silica-encapsulated NIR alloy quantum dots CdSeTe within short time

Silica-based near-infrared fluorescent materials in biological application have attracted much attention. But the current methods for preparing silica-encapsulated near-infrared radiation (NIR) quantum dots (QDs) are commonly time-consuming and can only obtain a few products in one batch. Herein, we present a fast and facile one-pot aqueous-phase route to prepare NIR-emitting silica-encapsulated CdSeTe QDs at large scale. The influences of various experimental conditions on the luminescent properties of the obtained silica hybrids QDs have been systematically investigated, such as capping agent, reaction time, pH value and so on. The final product has been characterized by X-ray diffraction, transmission electron microscope, photoluminescent spectra and energy dispersive x-ray spectroscopy (EDX). The silica-coated NIR-emitting QDs can be obtained within 10 h under the optimized conditions. The yield is 3.70 g in one batch. The final product is spherical with an average particle size around 15 nm.