Thermally induced phase transformation on 12-tungstophosphoric acid/ZrO2 sol-gel

J. G. Hernández-Cortéz; T. López; M. E. Manríquez; R. Gómez; J. Navarrete

doi:10.1023/A:1020794914686

Thermally induced phase transformation on 12-tungstophosphoric acid/ZrO₂ sol-gel

J. G. Hernández-Cortéz, T. López, M. E. Manríquez, R. Gómez, J. Navarrete

Research output: Contribution to journal › Article › peer-review

10 Scopus citations

Abstract

Zirconium (IV)-n-butoxide and tungstophosphoric acid (WP) were co-gelled at pH 3, 5 and 7 with HCl acid, C₂H₄O₂ acid and NH₄OH, respectively. Pyridine adsorption bands at 1610 and 1442 cm^-1 corresponding to Lewis acidic sites were observed by FTIR spectroscopy. Acidity determined by ammonia thermodesorption shows values around 1100 μmol of NH₃/g, which correspond to solids showing super acidity. It was found that the incorporation of WP to gelling zirconia delay the formation of tetragonal zirconia. Raman spectroscopy shows the stabilization of the Keggin structure on zirconia thermally treated at 400°C.

Original language	English
Pages (from-to)	213-216
Number of pages	4
Journal	Journal of Sol-Gel Science and Technology
Volume	26
Issue number	1-3
DOIs	https://doi.org/10.1023/A:1020794914686
State	Published - Jan 2003
Externally published	Yes

Keywords

FTIR pyridine adsorption on ZrO
Raman spectroscopy on sol-gel ZrO
Sol-gel synthesis
Tungstophosphoric acid
ZrO NH-TPD
ZrO sol-gel

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title = "Thermally induced phase transformation on 12-tungstophosphoric acid/ZrO2 sol-gel",

abstract = "Zirconium (IV)-n-butoxide and tungstophosphoric acid (WP) were co-gelled at pH 3, 5 and 7 with HCl acid, C2H4O2 acid and NH4OH, respectively. Pyridine adsorption bands at 1610 and 1442 cm-1 corresponding to Lewis acidic sites were observed by FTIR spectroscopy. Acidity determined by ammonia thermodesorption shows values around 1100 μmol of NH3/g, which correspond to solids showing super acidity. It was found that the incorporation of WP to gelling zirconia delay the formation of tetragonal zirconia. Raman spectroscopy shows the stabilization of the Keggin structure on zirconia thermally treated at 400°C.",

keywords = "FTIR pyridine adsorption on ZrO, Raman spectroscopy on sol-gel ZrO, Sol-gel synthesis, Tungstophosphoric acid, ZrO NH-TPD, ZrO sol-gel",

author = "Hern{\'a}ndez-Cort{\'e}z, {J. G.} and T. L{\'o}pez and Manr{\'i}quez, {M. E.} and R. G{\'o}mez and J. Navarrete",

note = "Funding Information: We thanks CONACyT (M{\'e}xico) for financial support (Beca No. 111633) and Instituto Mexicano del Petroleo.",

year = "2003",

month = jan,

doi = "10.1023/A:1020794914686",

language = "Ingl{\'e}s",

volume = "26",

pages = "213--216",

journal = "Journal of Sol-Gel Science and Technology",

issn = "0928-0707",

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TY - JOUR

T1 - Thermally induced phase transformation on 12-tungstophosphoric acid/ZrO2 sol-gel

AU - Hernández-Cortéz, J. G.

AU - López, T.

AU - Manríquez, M. E.

AU - Gómez, R.

AU - Navarrete, J.

N1 - Funding Information: We thanks CONACyT (México) for financial support (Beca No. 111633) and Instituto Mexicano del Petroleo.

PY - 2003/1

Y1 - 2003/1

N2 - Zirconium (IV)-n-butoxide and tungstophosphoric acid (WP) were co-gelled at pH 3, 5 and 7 with HCl acid, C2H4O2 acid and NH4OH, respectively. Pyridine adsorption bands at 1610 and 1442 cm-1 corresponding to Lewis acidic sites were observed by FTIR spectroscopy. Acidity determined by ammonia thermodesorption shows values around 1100 μmol of NH3/g, which correspond to solids showing super acidity. It was found that the incorporation of WP to gelling zirconia delay the formation of tetragonal zirconia. Raman spectroscopy shows the stabilization of the Keggin structure on zirconia thermally treated at 400°C.

AB - Zirconium (IV)-n-butoxide and tungstophosphoric acid (WP) were co-gelled at pH 3, 5 and 7 with HCl acid, C2H4O2 acid and NH4OH, respectively. Pyridine adsorption bands at 1610 and 1442 cm-1 corresponding to Lewis acidic sites were observed by FTIR spectroscopy. Acidity determined by ammonia thermodesorption shows values around 1100 μmol of NH3/g, which correspond to solids showing super acidity. It was found that the incorporation of WP to gelling zirconia delay the formation of tetragonal zirconia. Raman spectroscopy shows the stabilization of the Keggin structure on zirconia thermally treated at 400°C.

KW - FTIR pyridine adsorption on ZrO

KW - Raman spectroscopy on sol-gel ZrO

KW - Sol-gel synthesis

KW - Tungstophosphoric acid

KW - ZrO NH-TPD

KW - ZrO sol-gel

UR - http://www.scopus.com/inward/record.url?scp=0037268211&partnerID=8YFLogxK

U2 - 10.1023/A:1020794914686

DO - 10.1023/A:1020794914686

M3 - Artículo

AN - SCOPUS:0037268211

SN - 0928-0707

VL - 26

SP - 213

EP - 216

JO - Journal of Sol-Gel Science and Technology

JF - Journal of Sol-Gel Science and Technology

IS - 1-3

ER -

Thermally induced phase transformation on 12-tungstophosphoric acid/ZrO₂ sol-gel

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Keywords

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