Preparation of Carbonaceous Hemispheres Using a Hard Templating Approach.

ABSTRACT

Silica spheres prepared using a Stöber method were covered with 4,4'-biphenylene-bridged polybissilsesquioxane to form a core-shell structure. After carbonization, and the removal of the silica, carbonaceous hemispheres were obtained. The hemispheres were formed because of the collapse and shrinkage of the hollow spheres. The obtained samples were characterized using field-emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, X-ray diffraction, and nitrogen sorption measurements. The carbon was amorphous. Large numbers of micropores were identified in the hemispheres. The micropores were formed because of the removal of the silica. Spheres with a rattle-type structure were also found during the formation of the hollow carbonaceous spheres.