Nanoporous carbons from cypress I. Preparation and pore structure

Nanoporous carbons were prepared from cypress chips under a flow of super-heated steam, and their surface area reached more than 1000 m2/g without an additional activation process. Cypress charcoals prepared at a temperature of 800–870°C had a large external surface area of more than 400 m2/g, comparable to the microporous surface area, even though only 30–40 m2/g was obtained by carbonization in a flow of Ar gas. Cypress charcoals prepared above 900°C were microporous with a microporous surface area more than 800 m2/g and an external surface area of about 150 m2/g. The pore structure in cypress charcoals could be controlled by selecting the temperature of the steam.