Desorption kinetics of hydrogen and deuterium from Si(111) 7×7 studied using laser‐induced thermal desorption

1988 ◽  
Vol 89 (3) ◽  
pp. 1709-1718 ◽  
Author(s):  
B. G. Koehler ◽  
C. H. Mak ◽  
D. A. Arthur ◽  
P. A. Coon ◽  
S. M. George

The kinetics of associative desorption from mixed adlayers containing two kinds of particles (N and 0) have been examined. Standard statistical mechanical methods have been employed to study the effects of lateral interactions (ω NN , ω NO , ω OO ) between near-neighbour particles on the desorption kinetics while the adlayer stoichiometry varies continuously during a desorption sweep. Although the most general case ω NN ≠ ω NO ≠ ω OO ≠ 0) is found to be mathematically intractable, either one of two useful approximations can lead to analytic expressions for the desorption rate of N 2 , NO and O 2 . Both of these approximations have been used to simulate the thermal desorption spectra from a 1:1 layer of N and O atoms absorbed on Pt, Ni and Ru surfaces. The results show that, although the operation of lateral interactions can profoundly affect the desorption kinetics of these systems they cannot significantly alter the product distribution. N 2 and O 2 are overwhelmingly the major products, with NO desorption being entirely negligible in every case. We therefore conclude that observations of molecular NO in thermal desorption in these systems is evidence of molecularly adsorbed NO on the surface. Such desorption of NO is not due to recombination of surface N and O atoms. Reasonable values of the interaction parameters are used in model calculations which give a fairly good quantitative account of the available experimental data. The comparison with experiment leads to the conclusion that O-O repulsions are significant in every case. The N-N interaction is either zero or slightly attractive on Pt and Ni, but is very definitely repulsive on Ru.


2020 ◽  
Vol 686 ◽  
pp. 178554
Author(s):  
R. Ben David ◽  
T. Ohaion-Raz ◽  
G. Rafailov ◽  
A. Danon ◽  
Y. Finkelstein

1978 ◽  
Vol 78 (3) ◽  
pp. 545-564 ◽  
Author(s):  
J.P. Cowin ◽  
D.J. Auerbach ◽  
C. Becker ◽  
L. Wharton

1994 ◽  
Vol 303 (1-2) ◽  
pp. 1-15 ◽  
Author(s):  
H.J. Kreuzer ◽  
Zhang Jun ◽  
S.H. Payne ◽  
W. Nichtl-Pecher ◽  
L. Hammer ◽  
...  

Author(s):  
Mingwang Ma ◽  
Ruiyun Wan ◽  
Yuan Wang ◽  
Yanlin Cheng ◽  
Li Liang ◽  
...  

Thermal desorption spectroscopy (TDS) was used to study the thermal desorption kinetics of zirconium hydride films, which were deposited on molybdenum substrates and thermally charged with gas phase hydrogen. The observed desorption peaks were attributed to phase transforming steps. The activation energy and pre-exponential factor for desorption kinetics was estimated as 116 kJ/mol and 8762 s−1 according to Kissinger relation, respectively. A simulation of TDS spectra was made, which showed that the desorption process followed a first order kinetics. The kinetic parameters were then utilized to predict weight loss behavior at a temperature profile. Pressure effects that can potentially reduce the desorption rate were discussed.


2002 ◽  
Vol 66 (3) ◽  
pp. 797 ◽  
Author(s):  
Leslie J. Glover ◽  
Matthew J. Eick ◽  
Patrick V. Brady

2021 ◽  
Vol 235-236 ◽  
pp. 106646
Author(s):  
P. Ciffroy ◽  
L. Carasco ◽  
D. Orjollet ◽  
C. Simonucci ◽  
L. Février

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