Evaluation of hydrogen chemisorption in nanostructured carbon films by near edge X-ray absorption spectroscopy
Istituto di Fisiologia Generale e Chimica Biologica,
Università di Milano, via Trentacoste 2, 20134 Milano, Italy
2 Centro Interdisciplinare Materiali e Interfacce Nanostrutturati (CIMAINA), Università di Milano, Via Celoria 16, 20133 Milano, Italy
3 Dipartimento di Matematica, Università di Milano, via Saldini 50, 20133 Milano, Italy
4 Dipartimento di Fisica, Università di Milano, Via Celoria 16, 20133 Milano, Italy
Corresponding author: a firstname.lastname@example.org
Revised: 18 May 2005
Published online: 18 August 2005
We have developed a method for the quantitative evaluation of the chemisorbed fraction of hydrogen in nanostructured carbon films using Near Edge X-ray Absorption Spectroscopy (NEXAFS). In the carbon K-edge spectrum the peak related to carbon bonded to hydrogen is assumed to be correlated with the amount of hydrogen bonded to carbon. This assumption is supported by a comparative analysis of gas-phase hydrocarbons obtained via Electron Energy Loss Spectroscopy (EELS). We applied the method to nanostructured carbon (ns-C) films synthesized by supersonic cluster beam deposition. The evaluated quantity of chemisorbed hydrogen in different samples exposed to molecular hydrogen (pressure of 0.12 MPa, for 3 hours at room temperature) is wt.%.
PACS: 81.05.Uw – Carbon, diamond, graphite / 61.46+w – Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals / 61.10.Ht – X-ray absorption spectroscopy: EXAFS, NEXAFS, XANES, etc.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005