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The peculiar behaviour of zinc depending on whether it is used pure or alloyed in Cu63Zn37 wire electrodes leads either to nanosheets or to nanoparticles when it is processed by nanosecond pulsed discharges in liquid nitrogen. Using one electrode of copper and one electrode of zinc gives core-shell Cu@Zn nanoparticles but no alloy for the smallest nanoparticles (typically below 20 nm). Once nitrogen is evaporated, their oxidization in air produces Cu2O@ZnO nanoparticles. If both electrodes are made of Cu63Zn37, then the smallest nanoparticles are made of Cu and Zn and oxidized next in air to give Cu2O and ZnO nanoparticles. No alloy is formed either. Time-resolved optical emission spectroscopy gives clues on the origin of such behaviours, explaining why no alloy is formed when electrodes are made of different materials.

Increased interconnection between carbon nanofiller and ceramic support can give enhanced thermal conduction of a phase change material in thermal energy storage application. In the present work, we demonstrate a new strategy by directly growing the carbon nanofiller (i.e. graphene) on the surface of MgO ceramic via a chemical vapor deposition method forming a direct contact between them. This is realized by depositing a small amount of metal nanoparticles that catalyzes the growth of this carbon nanostructure on the surface of MgO. The successful synthesis of graphene was investigated by high resolution transmission electron microscopy and scanning electron microscopy. The thermal conductivity tests were performed using a transient plane source thermal characterization technique. We show that the material prepared by this method gives better heat conduction as compared to the individual mixing of these components.

This work presents a simple method to produce large quantities of crystallized antimony(0) nanoparticles through SbCl 3 chemical reduction using t -BuONa-activated sodium hydride. t -BuONa acts as a superficial stabilizer of Sb(0) nanoparticles inhibiting their growth and avoiding aggregation. The Sb(0) nanoparticles were characterized using transmission electron microscopy, XPS analysis and X-ray powder diffraction. Results obtained show that rhombohedral Sb(0) with diameters of ca. 4.7 ± 1.9 nm were produced. The influence of purification conditions on the aggregation state of Sb(0) particles is also described.