Defect related photocatalytic and photoluminescent characteristics of Gd-doped SnO2 nanoparticles with different shapes

Abstract

A new method for the preparation of Gd-doped SnO2 nanoparticles based on the precipitation method followed by hydrothermal treatment has been developed. Two different shape series of nanoparticles with different Gd content were obtained and fully characterized. Wide number of parameters, including lattice parameters, crystallite size, particle size, surface composition, oxygen vacancies, structural defects, band gap energy, luminescent spectra, band structure and density of states were determined.It was shown that the mechanism of oriented attachment of nanoparticle growth is stimulated during hydrothermal treatment. Quantum computer calculations of the interaction energies of oriented nanoparticles were performed and the role of ions in the reaction media was revealed.A study of the photoluminescence of the obtained nanoparticles was carried out, showing a blue photoluminescence corresponding to the oxygen vacancies, indicating their presence.Photocatalytic activity of nanoparticles when irradiated with visible light was shown, which is explained by quantum chemical calculations and demonstrated in the example of a colored solution of the organic dye methylene blue. The relation between the morphological and structural properties of nanoparticles and their photocatalytic properties has been studied in detail. A high degradation percentage is achieved using a regular commercially available LED lamp with a visible light spectrum.Novelty of the work lies in obtaining series of samples with various parameters, detailed studies of oriented attachment mechanism and impact of the nanoparticle parameters on photocatalytic properties. A concept for the development of efficient photocatalysts based on chemical and computational experiments is proposed.