The thermal decomposition of azomethane on Pt(111)

David Jentz, Michael Trenary, X. D. Peng, Peter C Stair

Research output: Contribution to journalArticle

59 Citations (Scopus)

Abstract

The thermal decomposition of azomethane, CH3N=NCH3, and methylamine, CH3NH2,on Pt(111) has been investigated by reflection absorption infrared spectroscopy (RAIRS) and temperature programmed reaction spectroscopy (TPRS). Using the surface dipole selection rule of RAIRS and comparing with the IR and Raman spectra of solidtrans-andcis-azomethane, we find thattrans-azomethane converts tocis-azomethane upon adsorbing onto the Pt(111) surface at 84 K. Additionally, we propose that thecis-azomethane tautomerizes to formaldehyde methylhydrazone, CH3NHN=CH2, which subsequently undergoes N-N bond cleavage between 200 and 275 K. Above 300 K aminomethylidyne, CNH2, is formed. Aminomethylidyne is also formed on the methylamine dosed surface. Cyanogen, C2N2(g), formed from the combination of CNads was also observed by TPRS as a minor reaction product. A comparison of the IR spectra of azomethane and methylamine dosed surfaces indicates the formation of chemisorbed methylamine as one intermediate in the decomposition of azomethane.

Original languageEnglish
Pages (from-to)282-294
Number of pages13
JournalSurface Science
Volume341
Issue number3
DOIs
Publication statusPublished - Nov 10 1995

Fingerprint

thermal decomposition
Pyrolysis
Absorption spectroscopy
Infrared spectroscopy
absorption spectroscopy
infrared spectroscopy
Spectroscopy
cyanogen
formaldehyde
Reaction products
Formaldehyde
reaction products
spectroscopy
Raman scattering
cleavage
Raman spectra
dipoles
Decomposition
decomposition
Temperature

Keywords

  • Azomethane
  • Chemisorption
  • Hydrogen cyanide
  • Low index single crystal surfaces
  • Metallic surfaces
  • Methylamine
  • Platinum
  • Reflection spectroscopy
  • Solid-gas interfaces
  • Thermal desorption
  • Vibrations of adsorbed molecules

ASJC Scopus subject areas

  • Materials Chemistry
  • Surfaces, Coatings and Films
  • Condensed Matter Physics
  • Surfaces and Interfaces
  • Physical and Theoretical Chemistry

Cite this

The thermal decomposition of azomethane on Pt(111). / Jentz, David; Trenary, Michael; Peng, X. D.; Stair, Peter C.

In: Surface Science, Vol. 341, No. 3, 10.11.1995, p. 282-294.

Research output: Contribution to journalArticle

Jentz, David ; Trenary, Michael ; Peng, X. D. ; Stair, Peter C. / The thermal decomposition of azomethane on Pt(111). In: Surface Science. 1995 ; Vol. 341, No. 3. pp. 282-294.
@article{06ddea750a1e49febf2a02c72c7309ae,
title = "The thermal decomposition of azomethane on Pt(111)",
abstract = "The thermal decomposition of azomethane, CH3N=NCH3, and methylamine, CH3NH2,on Pt(111) has been investigated by reflection absorption infrared spectroscopy (RAIRS) and temperature programmed reaction spectroscopy (TPRS). Using the surface dipole selection rule of RAIRS and comparing with the IR and Raman spectra of solidtrans-andcis-azomethane, we find thattrans-azomethane converts tocis-azomethane upon adsorbing onto the Pt(111) surface at 84 K. Additionally, we propose that thecis-azomethane tautomerizes to formaldehyde methylhydrazone, CH3NHN=CH2, which subsequently undergoes N-N bond cleavage between 200 and 275 K. Above 300 K aminomethylidyne, CNH2, is formed. Aminomethylidyne is also formed on the methylamine dosed surface. Cyanogen, C2N2(g), formed from the combination of CNads was also observed by TPRS as a minor reaction product. A comparison of the IR spectra of azomethane and methylamine dosed surfaces indicates the formation of chemisorbed methylamine as one intermediate in the decomposition of azomethane.",
keywords = "Azomethane, Chemisorption, Hydrogen cyanide, Low index single crystal surfaces, Metallic surfaces, Methylamine, Platinum, Reflection spectroscopy, Solid-gas interfaces, Thermal desorption, Vibrations of adsorbed molecules",
author = "David Jentz and Michael Trenary and Peng, {X. D.} and Stair, {Peter C}",
year = "1995",
month = "11",
day = "10",
doi = "10.1016/0039-6028(95)00727-X",
language = "English",
volume = "341",
pages = "282--294",
journal = "Surface Science",
issn = "0039-6028",
publisher = "Elsevier",
number = "3",

}

TY - JOUR

T1 - The thermal decomposition of azomethane on Pt(111)

AU - Jentz, David

AU - Trenary, Michael

AU - Peng, X. D.

AU - Stair, Peter C

PY - 1995/11/10

Y1 - 1995/11/10

N2 - The thermal decomposition of azomethane, CH3N=NCH3, and methylamine, CH3NH2,on Pt(111) has been investigated by reflection absorption infrared spectroscopy (RAIRS) and temperature programmed reaction spectroscopy (TPRS). Using the surface dipole selection rule of RAIRS and comparing with the IR and Raman spectra of solidtrans-andcis-azomethane, we find thattrans-azomethane converts tocis-azomethane upon adsorbing onto the Pt(111) surface at 84 K. Additionally, we propose that thecis-azomethane tautomerizes to formaldehyde methylhydrazone, CH3NHN=CH2, which subsequently undergoes N-N bond cleavage between 200 and 275 K. Above 300 K aminomethylidyne, CNH2, is formed. Aminomethylidyne is also formed on the methylamine dosed surface. Cyanogen, C2N2(g), formed from the combination of CNads was also observed by TPRS as a minor reaction product. A comparison of the IR spectra of azomethane and methylamine dosed surfaces indicates the formation of chemisorbed methylamine as one intermediate in the decomposition of azomethane.

AB - The thermal decomposition of azomethane, CH3N=NCH3, and methylamine, CH3NH2,on Pt(111) has been investigated by reflection absorption infrared spectroscopy (RAIRS) and temperature programmed reaction spectroscopy (TPRS). Using the surface dipole selection rule of RAIRS and comparing with the IR and Raman spectra of solidtrans-andcis-azomethane, we find thattrans-azomethane converts tocis-azomethane upon adsorbing onto the Pt(111) surface at 84 K. Additionally, we propose that thecis-azomethane tautomerizes to formaldehyde methylhydrazone, CH3NHN=CH2, which subsequently undergoes N-N bond cleavage between 200 and 275 K. Above 300 K aminomethylidyne, CNH2, is formed. Aminomethylidyne is also formed on the methylamine dosed surface. Cyanogen, C2N2(g), formed from the combination of CNads was also observed by TPRS as a minor reaction product. A comparison of the IR spectra of azomethane and methylamine dosed surfaces indicates the formation of chemisorbed methylamine as one intermediate in the decomposition of azomethane.

KW - Azomethane

KW - Chemisorption

KW - Hydrogen cyanide

KW - Low index single crystal surfaces

KW - Metallic surfaces

KW - Methylamine

KW - Platinum

KW - Reflection spectroscopy

KW - Solid-gas interfaces

KW - Thermal desorption

KW - Vibrations of adsorbed molecules

UR - http://www.scopus.com/inward/record.url?scp=0029406551&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029406551&partnerID=8YFLogxK

U2 - 10.1016/0039-6028(95)00727-X

DO - 10.1016/0039-6028(95)00727-X

M3 - Article

AN - SCOPUS:0029406551

VL - 341

SP - 282

EP - 294

JO - Surface Science

JF - Surface Science

SN - 0039-6028

IS - 3

ER -