Nano-CaO templated carbon by CVD: From nanosheets to nanocages

Nanostructured carbon with different morphologies are easily prepared by a chemical vapor deposition (CVD) process using nano-CaO as template and toluene as carbon precursor and followed by template removal with diluted hydrochloric acid. During the CVD process, the toluene are pyrolyzed to generate carbon atoms and then deposit on the surface of nano-CaO particles. With a CVD growth time less than 10 min, as the surface of the nano-CaO particles are only partly coated with a few layers of carbon atoms, the obtained carbon are small, thin nanosheets with a maximum surface area of 612 m(2) g(-1). As the CVD growth time prolonged to over 15 min, the pyrolyzed carbon atoms will coat the whole surface of the nano-CaO particles, yielding carbon nanocages with a maximum pore volume as high as 2.618 cm(3) g(-1) after template removal. (C) 2014 Elsevier B.V. All rights reserved.