Morphology, Microstructure and Transport Properties of ZnO Decorated SiO2 Nanoparticles (Preprint)

摘要

We report on a novel, surfactant free method to achieve nanocrystalline ZnO decoration of an SiO2 nanoparticle at ambient temperature. The size distribution of the naked and decorated SiO2 nanoparticles is measured by dynamic light scattering, and monodisperse distribution is observed for each. The morphology and microstructure of the nanoparticles are explored using atomic force microscopy and high resolution transmission electron microscopy. Investigation of the optical properties of the ZnO decorated SiO2 nanoparticles shows absorption of 350 nm. This blue shift in absorption compared to bulk ZnO nanocrystals. Finally, the electronic transport properties of the nanoparticles is explored by scanning conductance atomic force microscopy. A memristive hysteresis in the transport properties of the individual ZnO decorated SiO2 nanoparticles is observed. Optical absorption measurements suggest the presence of oxygen vacancies, the migration and annihilation of which appears to contribute to the dynamic conduction properties of the ZnO decorated nanoparticles. We believe this to be the first demonstration of a ZnO decorated SiO2 nanoparticle, and represents a simple yet powerful way of achieving the optical and electrical properties of ZnO combined with the simplicity of SiO2 synthesis.