Desorption Kinetics of Methanol from Al2O3(0001) Studied Using Temperature-Programmed Desorption and Isothermal Desorption

1998 ◽  
Vol 102 (35) ◽  
pp. 6831-6834 ◽  
Author(s):  
S. Y. Nishimura ◽  
R. F. Gibbons ◽  
N. J. Tro
Keyword(s):  
Temperature Programmed Desorption ◽  
Desorption Kinetics ◽  
Temperature Programmed ◽  
Kinetics Of

scholarly journals Engineering of TMDC-OSC Hybrid Interfaces: The Thermodynamics of Unitary and Mixed Acene Monolayers on MoS2

2020 ◽  
Author(s):  
Stefan R. Kachel ◽  
Pierre Martin Dombrowski ◽  
Tobias Breuer ◽  
Michael Gottfried ◽  
Gregor Witte
Keyword(s):  
Monte Carlo ◽  
Molecular Mobility ◽  
Temperature Programmed Desorption ◽  
Model System ◽  
Desorption Kinetics ◽  
Temperature Programmed ◽  
Kinetics Of

Here, we use temperature-programmed desorption (TPD) and Monte Carlo (MC) simulations<br>of TPD traces to characterize the desorption kinetics of pentacene (PEN) and perfluoropentacene (PFP) on MoS2 as a model system for OSCs on TMDCs. We show that the monolayers of PEN and PFP are thermally stabilized compared to their multilayers, which allows to prepare nominal monolayers by selective desorption of multilayers. This stabilization is, however, caused by entropy due to a high molecular mobility rather than an enhanced molecule-substrate bond. Consequently, the nominal monolayers are not densely packed films.

scholarly journals Engineering of TMDC-OSC Hybrid Interfaces: The Thermodynamics of Unitary and Mixed Acene Monolayers on MoS2

2020 ◽  
Author(s):  
Stefan R. Kachel ◽  
Pierre Martin Dombrowski ◽  
Tobias Breuer ◽  
Michael Gottfried ◽  
Gregor Witte
Keyword(s):  
Monte Carlo ◽  
Molecular Mobility ◽  
Temperature Programmed Desorption ◽  
Model System ◽  
Desorption Kinetics ◽  
Temperature Programmed ◽  
Kinetics Of

Here, we use temperature-programmed desorption (TPD) and Monte Carlo (MC) simulations<br>of TPD traces to characterize the desorption kinetics of pentacene (PEN) and perfluoropentacene (PFP) on MoS2 as a model system for OSCs on TMDCs. We show that the monolayers of PEN and PFP are thermally stabilized compared to their multilayers, which allows to prepare nominal monolayers by selective desorption of multilayers. This stabilization is, however, caused by entropy due to a high molecular mobility rather than an enhanced molecule-substrate bond. Consequently, the nominal monolayers are not densely packed films.

Competitive Pairing and the Chemistry of Coadsorbed Hydrogen and Halogens on Ge(100)

1992 ◽  
Vol 282 ◽  
Author(s):  
Yuemei L. Yang ◽  
Stephen M. Cohen ◽  
Mark P. D'Evelyn
Keyword(s):  
Epitaxial Growth ◽  
Atomic Layer ◽  
Temperature Programmed Desorption ◽  
Model System ◽  
Atomic Layer Epitaxy ◽  
Desorption Kinetics ◽  
First Order ◽  
First Order Kinetics ◽  
Temperature Programmed ◽  
Kinetics Of

ABSTRACTThe chemistry of coadsorbed H and X (X=C1, Br) on semiconductor surfaces is important in epitaxial growth of silicon from chlorosilanes and of SixGe1−x alloys, in hydrogenating/ halogenating cycles in atomic layer epitaxy, and also provides an interesting model system, yet has received little attention to date. We have investigated the interaction of HC1 and HBr with Ge(100) by temperature-programmed desorption, and find that H2, HCl and HBr each desorb with near-first-order kinetics near 570–590 K and that GeCl2 and GeBr2 desorb with near-second-order kinetics near 675 K and 710 K, respectively. Analysis of the desorption kinetics of H2 and HX provides evidence that adsorbed H and X atoms pair preferentially in a qualitatively similar way as H atoms adsorbed alone on Ge(100)2×1 or Si(100)2×1 and that pairing of H+X occurs in competition with pairing of H+H.

Adsorption of Silicon Tetrachloride on Si(111) 7×7

1988 ◽  
Vol 131 ◽  
Author(s):  
P. Gupta ◽  
P. A. Coon ◽  
B. G. Koehler ◽  
S. M. George
Keyword(s):  
Surface Temperature ◽  
Thermal Desorption ◽  
Temperature Programmed Desorption ◽  
Silicon Tetrachloride ◽  
Sticking Coefficient ◽  
Adsorption Model ◽  
Temperature Programmed ◽  
Kinetics Of

ABSTRACTThe kinetics of SiCl4 adsorption on Si(lll) 7×7 were studied using laser induced thermal desorption (LITD) and temperature programmed desorption (TPD) techniques. The initial reactive sticking coefficient of SiCl4 on Si(lll) 7×7 was observed to decrease with increasing surface temperature. This decrease was consistent with a precursor-mediated adsorption model. Both LITD and TPD experiments monitored SiCl2 as the main desorption product. These results suggest that SiC12 may be the stable chlorine species on the Si(lll) 7×7 surface.

Adsorption and Desorption Kinetics for Chlorosilanes on Si(111) 7×7

1990 ◽  
Vol 204 ◽  
Author(s):  
P. Gupta ◽  
P.A. Coon ◽  
B.G. Koehler ◽  
M.L. Wise ◽  
S.M. George
Keyword(s):  
Activation Energy ◽  
Surface Coverage ◽  
Temperature Programmed Desorption ◽  
Desorption Kinetics ◽  
Sticking Coefficient ◽  
Temperature Dependent ◽  
Adsorption And Desorption ◽  
Desorption Activation Energy ◽  
Temperature Programmed ◽  
Sticking Coefficients

ABSTRACTThe adsorption and desorption kinetics for SiCl4 and SiCl2H2 on Si(111) 7×7 were studied using laser-induced thermal desorption (LITD) and temperature programmed desorption (TPD) techniques. Both LITD and TPD experiments monitored SiCl2 as the main desorption product at 950 K at all coverages of SiCl4 and SiCl2H2 on Si(111) 7×7.HC1 desorption at 850 K and H2 desorption at 810 K were also observed following SiCl2H2 adsorption. Isothermal LITD measurements of SiCl4 and SiCl2H2) adsorption on Si(111) 7×7 revealed that the initial reactive sticking coefficient decreased with increasing surface temperature for both molecules. The temperature-dependent sticking coefficients were consistent with precursor-mediated adsorption kinetics. Isothermal LITD studies of SiC12 desorption revealed second-order SiCl2 desorption kinetics. The desorption kinetics were characterizedby a desorption activation energy of Ed = 67 kcal/mol and a preexponential of vd = 3.2 cm2/s. TPD studies observed that the HCI desorption yield decreased relative to H2 and SiCl2 desorption as a function of surface coverage following SiCl2H2 exposure. These results indicate that when more hydrogen desorbs as H2 at higher coverages, The remaining chlorine is forced to desorb as SiCl 2.

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