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Summary
On this work, an efficient methodology of study of thermal desorption spectra (TDS) of hydrogen in carbon supplies was additional developed and utilized. The methodology makes it potential, from TDS knowledge of 1 heating price, to find out the activation energies and pre-exponential elements of the speed constants of desorption processes. The TDS knowledge of Rajasekaran et al. for hydrogenated epitaxial graphenes with a diamond-like construction (as in graphane) have been analyzed. Some new data was obtained concerning the states of hydrogen in such uncommon buildings. It was proven that about half of the hydrogen contained within the samples is localized within the interfacial areas (between graphene and the substrate), whereas the desorption of such hydrogen is proscribed by diffusion (with three activation energies (34 kJ/mol(H2), 45 kJ/mol(H2), and 68 kJ/mol(H2)) of hydrogen molecules in these areas to the lateral surfaces of the samples. It was additionally proven that the remainder of the hydrogen is localized on the highest floor of the samples, whereas desorption of hydrogen atoms happens with two activation energies and frequency elements (174 kJ/mol(H), 2 × 1013 s−1, and 256 kJ/mol(H), 3 × 1018 s−1); the obtained portions are corresponding to the associated traits for graphane.
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