Controlled synthesis of carbon-encapsulated copper nanostructures by using smectite clays as nanotemplates

Rhomboidal and spherical metallic-copper nanostructures were encapsulated within well-formed graphitic shells by using a simple chemical method that involved the catalytic decomposition of acetylene over a copper catalyst that was supported on different smectite clays surfaces by ion-exchange. These metallic-copper nanostructures could be separated from the inorganic support and remained stable for months. The choice of the clay support influenced both the shape and the size of the synthesized Cu nanostructures. The synthesized materials and the supported catalysts from which they were produced were studied in detail by TEM and SEM, powder X-ray diffraction, thermal analysis, as well as by Raman and X-ray photoelectron spectroscopy. Differently shaped Cu nanostructures were encapsulated within graphite shells by using a simple chemical method that involved the catalytic decomposition of acetylene over Cu catalysts that were supported on different smectite clay surfaces. The Cu nanostructures could be separated from the support and remained stable for months. The choice of clay support influenced the shape and size of the Cu nanostructures.