Regulation and prediction of defect-related properties in ZnO nanosheets: synthesis, morphological and structural parameters, DFT study and QSPR modelling

Abstract

The work is aimed to consider photocatalytic efficiency and photoluminescence dependence on oxygen vacancies and other crystal lattice defects in ZnO nanosheets in order to provide their regulation and perdictionA synthesis via precipitation method under different conditions followed by hydrothermal treatment under different temperatures to obtain series of nanosheet samples with various amounts of defects was performed. Obtained samples were fully characterized (SEM, XRD, FTIR, XPS, Raman, absorbance spectra). A novel approach has been proposed and applied to determine the amount of oxygen vacancies and defects from XPS and Raman spectroscopy data. Quantum-chemical calculations (DFT) were performed to obtain density of states and band structure and to study the impact of lattice parameters and oxygen vacancies on electronic structure.The photocatalytic properties under UV and visible light irradiation were studied. Relations between morphological, structural parameters and functional properties (photoluminescent and photocatalytic) of ZnO nanosheets using quantitative structure–property relationship (QSPR) method were established. The impact of defects in combinations with other parameters on functional properties was demonstrated. Revealed dependencies and QSPR model provide a possibility to predict functional properties of nanosheets can be used for the development of new materials.