Journal of Colloid and Interface Science, Vol.415, 7-12, 2014
One-pot synthesis of multicolor MnSe:ZnSe nanocrystals for optical coding
Though the investigation on controlling the fluorescence properties of nanocrystals (NCs) with single emission has been widely reported, few efforts were spent on adjusting the fluorescence properties of NCs with multiple emission peaks. In this work, we successfully synthesized multicolor MnSe:ZnSe NCs with multiple emission peaks and developed a simple and accurate method to realize photoluminescence (PL) spectra (or color) adjustment. The PL of MnSe:ZnSe NCs has two distinct emission peaks, the trap emission of ZnSe at 475 nm and Mn2+-induced emission at 585 nm. By adjusting the nucleation temperature, the emission color of the NCs can be encoded according to the ratio of the emission intensities at 475 and 585 nm. With the nucleation temperature rising from 0 to 70 degrees C, the PL ratio between trap emission and Mn2+-induced emission can be consecutively changed from (1, 3) to (1, 0.5). In addition, the trap state is deeply inside the NCs rather than on NCs surface so that the trap emission is stable during environment change. Thus, these MnSe:ZnSe NCs hold great promise as novel single-particle coding labels for biomedical imaging. (C) 2013 Elsevier Inc. All rights reserved.
Keywords:Multiple emission peaks;Nucleation temperature;MnSe aggregates;Single-particle coding labels