On the kinetic analysis of the hydrogen thermal desorption spectra for graphite and advanced carbon nanomaterials

Abstract

This study is devoted to a further development and application of our previous results, including the method of kinetic analysis of the hydrogen thermal desorption spectra (TDS) processes in materials heating with only one rate. As shown in this study, from such TDS data, the activation energies (Q) and the per-exponential factors (K0) of the rate constants (K) of the hydrogen desorption processes can be determined (evaluated with the enough accuracy) with the help of our method, including the standard deconvolution of TDS spectra by “pure” (that’s symmetrical) Gaussian curves (peaks), along with the identification (interpretation) of the peaks, and revealing their atomic mechanisms. Some critical aspects of using the pure Gaussian curves approach, and/or the first order reactions Kissinger approach (that’s is asymmetrical curves), especially for the diffusion controlling cases, along with approaches of Polanyi–Wigner equation of the first-order processes (that’s asymmetrical curves) and the second order processes (that’s symmetrical curves) are taken into account, as well. As an example, such a treatment and identification (interpretation) of TDS data on deuterium TDS spectra for graphite exposed to high flux plasma at high temperatures have been performed.