In-situ transmission electron microscopy study of melting and diffusion processes at the nanoscale in ZnO nanotubes with Sn cores

The thermal behaviour of ZnO nanotubes partially filled with Sn cores, containing also Sn nanoclusters and nanovoids, has been investigated by in-situ heating treatments in a transmission electron microscope (TEM). The size effect on the melting temperature of Sn nanoclusters and nanorods, and diffusion of voids along the nanotube axis have been studied by directly recording the TEM images during heating treatments. Melting temperatures of 163 °C and 213 °C were found for a 10 nm diameter particle and a 30 nm diameter Sn core respectively. Different diffusion processes in the Sn-ZnO core/shell structure at 640 °C are described.