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Method of thermal desorption study of hydrogen states in carbon materials and nanomaterialsa I.P. Bardin Central Research Institute for Ferrous Metallurgy, Scientific Center of Metals Science and Physics, Radio Str., 23/9, Build. 2, Moscow, 105005, Russian Federation b St. Petersburg State University, Universitetskaya naberezhnaya, 7 - 9, St. Petersburg, 199034, Russian Federation c Togliatti State University, Research Institute of Progressive Technologies, Belorusskaya Str., 14b, Togliatti, 445020, Russian Federation d Institute of Applied Mathematical Research of the Karelian Research Centre of the Russian Academy of Sciences, Pushkinskaya str., 11, Petrozavodsk, Republic of Karelia, 185910, Russian Federation e Ioffe Institute, ul. Polytekhnicheskaya 26, St. Petersburg, 194021, Russian Federation An efficient technique for processing, analyzing, and interpreting thermal desorption spectra (TDSs) of hydrogen in carbon materials and nanomaterials obtained using a single heating rate is developed, which makes it possible to study various states of hydrogen and determine the characteristics corresponding to them, including the rate constants and activation energies of desorption processes. The method is no less informative, but much less laborious from the experimental point of view, than the generally accepted (to determine such characteristics) Kissinger method, which requires using several heating rates and has strict limits on applicability. The developed technique is based on approximating the hydrogen TDS by Gaussians and processing their peaks in the approximation of first and second order reactions. The technique includes the use of nonstandard criteria of `likelihood' and/or `physicality' of the results, as well as verification and/or refinement of the results by numerical modeling methods that allow approximating TDSs not by Gaussians but by curves corresponding to first or second order reactions.
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