Temperature-dependent interfacial behaviour of Au@SiO2 core shell nanoparticles on Si3N4 support film

Abstract

Structural, chemical, and thermodynamic behaviours of metallic nanostructures surrounded by a variety of ceramic/refractory materials play a crucial role in their high-temperature applications. In this work, we report the effect of high-temperature annealing on a system of Au@SiO2 core-shell nanoparticles dispersed on Si3N4 grids. The thermal degradation of the Au–SiO2–Si3N4 system has been explained using minute compositional changes at different interfaces involving Au–SiO2, SiO2–Si3N4 and Au–Si3N4. High Angle Annular Dark Field Imaging coupled with Energy Dispersive X-ray Spectroscopy elemental mapping technique has been used for the same. Possible reactions among SiO2 and Si3N4 substrate with the aid of Au at high temperature leading to thermal decomposition of the system have been explained using High-Resolution Transmission Electron Microscopy and Selected Area Electron Diffraction analysis.