Investigation on the phosphine-free synthesis of CdSe nanocrystals by cadmium precursor injection

A green route for the synthesis of high quality zinc blende CdSe nanocrystals has been successfully established by using phosphine-free Se precursors combined with a cadmium precursor injection method. The effects of using different Se precursors, and adjustment of the molar ratios between the Cd and Se precursors have been investigated in detail to optimize the synthesis conditions. Absorption and photoluminescence (PL) spectra, X-ray diffraction (XRD), and transmission electron microscopy (TEM) were used for the characterization of synthesized CdSe nanocrystals. High brightness with the photoluminescence quantum yields up to 50% and narrow size-distribution with the full width at half-maximum (FWHM) below 24 nm were obtained under the optimized conditions. More than 5 g of high quality CdSe nanocrystals have been synthesized in one large scale reaction.