General strategy for embedding high quality Fe_3O_4 quantum dots and ZnS:Mn~(2+) quantum dots in a silica matrix

摘要

AbstractIn this paper, ZnS:Mn2+quantum dots (QDs) Fe3O4quantum dots (QDs)/SiO2nanocomposites were successfully synthesized by reverse microemulsion method. The average diameter of ZnS:Mn2+QDs, Fe3O4QDs and ZnS:Mn2+QDs Fe3O4QDs/SiO2nanocomposites was about 5.8, 9 and 29 nm, respectively. As the mass ratio of ZnS:Mn2+to Fe3O4QDs increased from 2.5:4 to 7.5:4, the intensity of the yellow–orange emission coming from Mn2+ions was increased. The superparamagnetic property of ZnS:Mn2+QDs Fe3O4QDs/SiO2nanocomposites was observed at room temperature, and the saturation magnetization was decreased as the amount of ZnS:Mn2+QDs increased.