A simplified synthesis of N-doped zeolite-templated carbons, the control of the level of zeolite-like ordering and its effect on hydrogen storage properties

Nitrogen-doped, microporous carbon materials have been prepared using zeolite EMC-2 as a hard template and acetonitrile as the carbon source via chemical vapour deposition (CVD) in the temperature range 700-950 degrees C. The carbon products exhibited high surface areas (up to 3360 m(2)/g), high pore volumes (up to 1.71 cm(3)/g) and had zeolite-like structural ordering derived from the template. The carbons had XRD patterns that exhibited two well resolved peaks and TEM images that showed well ordered pore channels. A high proportion of porosity (up to 85% of surface area and 73% of pore volume) for the best ordered carbon arose from micropores that exhibited narrow size distribution in the range 5-15 angstrom. The carbons generally retained the morphology of the template with solid-core particles at CVD temperatures up to 900 degrees C and hollow shells at 950 degrees C. The carbons had total hydrogen storage capacities up to 6.0 wt.% at -196 degrees C and 20 bar. The hydrogen uptake was found to be dependent on the level of zeolite-like ordering and the resulting textural properties. Particularly, high levels of zeolite-like ordering favoured micropores of size <15 angstrom which are favourable for higher hydrogen uptake capacities. (C) 2010 Elsevier Ltd. All rights reserved.