Preparation and characteristic analysis of carbon coated nanoscale SnO₂ system: an integrated experimental and first principles approach

Abstract

A successful preparation of carbon coated (CC- SnO2)and uncoated (UC- SnO2) nanoscale SnO2 is achieved via cost-effective physicochemical method employing polyvinyl alcohol (PVA) as the source of carbon. The idea of coating with carbon is to reduce agglomeration and investigate single particle properties. The resulting phase compositions of UC- and CC- SnO2 is characterized by XRD, Raman, TEM, UV-Vis, photoluminescence, dielectric- spectroscopy and conductivity measurement. The carbon coated SnO2 finds advancement in its characteristic properties with versatility, like phase and material stability, increase in activation energy and reduction in agglomeration formation. The prepared CC- SnO2 suppresses the natural mode of vibration of SnO2 nanoparticles. Dielectric spectroscopy measurements show that the dielectric loss is more in UC- SnO2 than CC- SnO2 at all frequencies. The existence of carbon coating on SnO2 nanoparticles and its phenomenal characterizing behavior was verified by first- principles approach with investigation of the structural and electronic properties of SnO2, PVA, and their merged structures. A model has been used to observe the surface interaction effect between SnO2 and PVA for a defined geometry elucidated through variations in the density of states results. The reported method and investigations approached through the integrated technique provides conspicuous enrichment to the field. Keywords: oxides; coatings; dielectric properties; first principles.