Thermolytic Growth of Zinc Sulfide Quantum Dots in Ethylene-Vinyl Acetate Matrix Utilizing Zinc Pyrrolidinedithiocarbamate

摘要

We present the formation of ZnS quantum dots in ethylene-vinyl acetate (EVA) matrix using the thermolysis process of zinc pyrrolidinedithiocarbamate (ZnPDTC). The annealing time and precursor concentration showed no significant effect on the radius of the quantum dots, but there is a significant difference seen on the annealing temperature at 220°C. Quantum confinement effect in semiconductor quantum dots of ZnS has been studied using the Brus Equation. Results showed that ground state confinement energy is inversely proportional to the size (radius) and exhibited a strong quantum confinement. The absorption peak of the obtained quantum dots showed in the range of 310-330 nm, a blue shift compared to that of the ZnS crystal structure. Growth kinetics follows the linear relationship of the third power of the particle size versus the time and a diffusion-limited Ostwald ripening mechanism was involved.