Reconnaissance of the specific surface of vapour grown carbon micro and nanofibres as a main controller of the sorption of hydrogen

Abstract

The influence of the hydrogen content in several physical aspects of carbonaceous microfibres obtained from a mixture of hydrogen and hydrocarbon gas is examinated in this study. The hydrogen content is evaluated behalf a measurement of the fibres density. These changes of content depend on the manufacturing process and further treatments of the fibres. The surface energy is established after contact angle evaluation. There is not a clear relation between the surface energy and the porosity, which is a very relevant parameter in order to establish the hydrogen storage capacity of all materials. The fibres have been evaluated using Kelvin probe force microscopy (KPFM), which provides a map of the surface potential. These measurements suggest a relation between the surface potential and the hydrogen adsorbed in the surface of the fibres. © 2010 Elsevier B.V. All rights reserved.