Surface modification and fluorescent properties of Mn2+-doped and undoped ZnS nanoparticles

Abstract

ZnS nanoparticles and Mn²⁺-doped ZnS nanoparticles were prepared by a reverse micelle reaction system. In addition, ZnS and Mn²⁺-doped ZnS nanoparticles were modified with poly(vinyl alcohol) (PVA) and 1-dodecanethiol (C₁₂H₂₅SH). The average particle size of the ZnS sample is determined around 2.3 nm by using the well-known Scherrer equation, which is in accordance with the results obtained from UV–vis and TEM analysis. Fluorescence intensity of the Mn²⁺-doped ZnS nanoparticles increases with increasing Mn²⁺ content compared with undoped ZnS nanoparticles, and coating PVA can also make fluorescence intensity increase. Different Zn²⁺/S^2- or C₁₂H₂₅SH/Zn²⁺ can affect intensity of PL emission peak and its position, which is discussed in this paper.