QUANTUM-CHEMICAL SIMULATION OF INTERACTIONS IN OPTICAL MATERIALS BASED ON SEMICONDUCTOR QUANTUM DOTS OF ZINC SULFIDE AND SOME POLYMERS

Functional materials based on quantum dots are specific nanomaterials with unique sets of electronic and optical properties due to the manifestation of the quantum-size effect. Quantum-chemical simulation is an effective tool for studying the physical and chemical characteristics of the studying objects, detailed analysis of their structural features and establishing patterns of system behavior in various external conditions. This work is aimed at assessing the possibilities of quantum-chemical study of the interactions between semiconductor zinc sulfide quantum dots and some polymers for optical materials. In this study, a quantum-chemical calculation of the molecular structure of the polymers' monomer units was performed, a method for the simulation of the structure and electronic properties of zinc sulfide quantum dots was selected. According to the simulation results the interactions between quantum dots and polymer samples, the influence of the polymers' nature and their functional groups on the properties of nanoparticles, the efficiency of their radiation and the features of their application in optoelectronics were studied. A comparative analysis of the calculated and experimental data on the geometric parameters and electronic properties of quantum dots was made. The calculation results indicate the possibility of changing the width of the forbidden zone of quantum dots by introducing polymers as surface agents, which affects the optical characteristics and potential application of these materials. According to the calculations, the polymer containing amino groups has the highest binding energy to the surface of quantum dots, compared to other compounds. The use of a shell made of this polymer can ensure high stability of the sizes and properties of nanoparticles, and contribute to an increase in the quantum yield of the material's light emission.