Surface investigation on thermal stability of tungstophosphoric acid supported on MCM-41 using synchrotron radiation

Pasl A. Jalil, Nouar Tabet, M. Faiz, N. M. Hamdan, Z. Hussain

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

The surface of supported tungstophosphoric acid H3PW 12O40 (HPW) on all-silica MCM-41 has been investigated using high-resolution X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES). The results show the interaction between HPW and MCM-41 upon impregnation. Nuclear magnetic resonance (NMR) spectroscopy results also seem to confirm the above conclusion. Heating the supported acid increased the structural damage of HPW and MCM-41. Our results also suggest the formation of tungsten oxides on the surface upon heat treatment at 400°C. A detailed analysis of the infrared (IR) spectra showed a gradual increase in the absorbance of the W-O-W corner shared vibration relative to the absorbance of the other bands. This indicates that the symmetry, and hence the stability of the bulk molecules were also decreased upon heating.

Original languageEnglish
Pages (from-to)1-6
Number of pages6
JournalApplied Catalysis A: General
Volume257
Issue number1
DOIs
Publication statusPublished - 10 Jan 2004
Externally publishedYes

Fingerprint

Multicarrier modulation
Synchrotron radiation
Thermodynamic stability
Acids
Heating
X ray absorption
Impregnation
Silicon Dioxide
Nuclear magnetic resonance spectroscopy
Tungsten
X ray photoelectron spectroscopy
Heat treatment
Silica
Infrared radiation
Molecules
Oxides
MCM-41

Keywords

  • HPWO
  • IR
  • MCM-41
  • Tungstophosphoric acid
  • XANES
  • XPS

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology

Cite this

Surface investigation on thermal stability of tungstophosphoric acid supported on MCM-41 using synchrotron radiation. / Jalil, Pasl A.; Tabet, Nouar; Faiz, M.; Hamdan, N. M.; Hussain, Z.

In: Applied Catalysis A: General, Vol. 257, No. 1, 10.01.2004, p. 1-6.

Research output: Contribution to journalArticle

@article{a01514e569ca4878bad199def556f95d,
title = "Surface investigation on thermal stability of tungstophosphoric acid supported on MCM-41 using synchrotron radiation",
abstract = "The surface of supported tungstophosphoric acid H3PW 12O40 (HPW) on all-silica MCM-41 has been investigated using high-resolution X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES). The results show the interaction between HPW and MCM-41 upon impregnation. Nuclear magnetic resonance (NMR) spectroscopy results also seem to confirm the above conclusion. Heating the supported acid increased the structural damage of HPW and MCM-41. Our results also suggest the formation of tungsten oxides on the surface upon heat treatment at 400°C. A detailed analysis of the infrared (IR) spectra showed a gradual increase in the absorbance of the W-O-W corner shared vibration relative to the absorbance of the other bands. This indicates that the symmetry, and hence the stability of the bulk molecules were also decreased upon heating.",
keywords = "HPWO, IR, MCM-41, Tungstophosphoric acid, XANES, XPS",
author = "Jalil, {Pasl A.} and Nouar Tabet and M. Faiz and Hamdan, {N. M.} and Z. Hussain",
year = "2004",
month = "1",
day = "10",
doi = "10.1016/j.apcata.2003.02.001",
language = "English",
volume = "257",
pages = "1--6",
journal = "Applied Catalysis A: General",
issn = "0926-860X",
publisher = "Elsevier",
number = "1",

}

TY - JOUR

T1 - Surface investigation on thermal stability of tungstophosphoric acid supported on MCM-41 using synchrotron radiation

AU - Jalil, Pasl A.

AU - Tabet, Nouar

AU - Faiz, M.

AU - Hamdan, N. M.

AU - Hussain, Z.

PY - 2004/1/10

Y1 - 2004/1/10

N2 - The surface of supported tungstophosphoric acid H3PW 12O40 (HPW) on all-silica MCM-41 has been investigated using high-resolution X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES). The results show the interaction between HPW and MCM-41 upon impregnation. Nuclear magnetic resonance (NMR) spectroscopy results also seem to confirm the above conclusion. Heating the supported acid increased the structural damage of HPW and MCM-41. Our results also suggest the formation of tungsten oxides on the surface upon heat treatment at 400°C. A detailed analysis of the infrared (IR) spectra showed a gradual increase in the absorbance of the W-O-W corner shared vibration relative to the absorbance of the other bands. This indicates that the symmetry, and hence the stability of the bulk molecules were also decreased upon heating.

AB - The surface of supported tungstophosphoric acid H3PW 12O40 (HPW) on all-silica MCM-41 has been investigated using high-resolution X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES). The results show the interaction between HPW and MCM-41 upon impregnation. Nuclear magnetic resonance (NMR) spectroscopy results also seem to confirm the above conclusion. Heating the supported acid increased the structural damage of HPW and MCM-41. Our results also suggest the formation of tungsten oxides on the surface upon heat treatment at 400°C. A detailed analysis of the infrared (IR) spectra showed a gradual increase in the absorbance of the W-O-W corner shared vibration relative to the absorbance of the other bands. This indicates that the symmetry, and hence the stability of the bulk molecules were also decreased upon heating.

KW - HPWO

KW - IR

KW - MCM-41

KW - Tungstophosphoric acid

KW - XANES

KW - XPS

UR - http://www.scopus.com/inward/record.url?scp=0346394261&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0346394261&partnerID=8YFLogxK

U2 - 10.1016/j.apcata.2003.02.001

DO - 10.1016/j.apcata.2003.02.001

M3 - Article

AN - SCOPUS:0346394261

VL - 257

SP - 1

EP - 6

JO - Applied Catalysis A: General

JF - Applied Catalysis A: General

SN - 0926-860X

IS - 1

ER -