KINETIC-PARAMETERS OBTAINED FROM AREA INTEGRATION OF SINGLE PEAK THERMAL-DESORPTION SPECTRA

This paper presents a method to analyze thermal desorption spectra based on area integration of the desorption peaks. An expression is derived for the rate of desorption in a thermal-activated process which permits evaluation of the rate from the intensity and area values for each point of the curve. Arrhenius plots of the rate data yield the activation energy and attempt frequency for desorption. The order of the desorption process is determined from the best linear fit in the Arrhenius plots. Included are applications for analyzing thermal desorption spectra obtained with a thermal conductivity detector or a mass spectrometer. Analyses of NO desorption from KNbO3 and H 2 desorption from Ni surfaces illustrate the method. © 1990 American Institute of Physics.