Microwave-assisted low temperature synthesis of wurtzite ZnS quantum dots

In this work we report, for the first time, on microwave assisted synthesis of wurtzite ZnS quantum dots (QDs) in controlled reaction at temperature as low as 150°C. The synthesis can be done in different microwave absorbing solvents with multisource or single source precursors. The QDs are less than 3nm in size as characterized by transmission electron microscopy (TEM) using selected area electron diffraction (SAED) patterns to confirm the wurtzite phase of ZnS QDs. The optical properties were investigated by UV–Vis absorption which shows blue shift in absorption compared to bulk wurtzite ZnS due to quantum confinement effects. The photoluminescence (PL) spectra of QDs reveal point defects related emission of ZnS QDs. Microwave assisted synthesis of wurtzite ZnS quantum dots (QDs) have been achieved in controlled reaction at temperature as low as 150°C. The synthesis was performed in different microwave absorbing solvents with multisource or single source precursors for very short reaction periods due to effective heating with microwaves. [Display omitted] ► Wurtzite a high temperature phase of ZnS was synthesized at low temperature. ► Low temperature synthesis was possible because of the use of microwave absorbing solvents. ► Capping agent was used to control the size of Quantum Dots. ► Two different systems were developed using single molecular precursor and multisource precursors