Characterization of molybdenum monomeric oxide species supported on hydroxylated silica: a DFT study

被引：44

作者：

Guesmi, Hazar ^{[1
]}

Grybos, Robert ^{[2
]}

Handzlik, Jaroslaw ^{[3
]}

Tielens, Frederik ^{[4
]}

机构：

[1] Ecole Natl Super Chim Montpellier, Inst Charles Gerhardt Montpellier, UMR 5253, CNRS ENSCM UM2 UM1, F-34296 Montpellier, France

[2] J Haber Inst Catalysis & Surface Chem, PL-30239 Krakow, Poland

[3] Cracow Univ Technol, Fac Chem Engn & Technol, PL-31155 Krakow, Poland

[4] Sorbonne Univ, Univ Paris 06, Coll France,UMR 7574, Lab Chim Matiere Condensee, F-75231 Paris 05, France

来源：

PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 2014年 / 16卷 / 34期

关键词：

INITIO MOLECULAR-DYNAMICS; AB-INITIO; FRAMEWORK SITES; RAMAN-SPECTROSCOPY; SURFACE-STRUCTURES; CATALYTIC-ACTIVITY; MO/SIO2; CATALYSTS; PARTIAL OXIDATION; MECHANISM; ZEOLITES;

D O I：

10.1039/c4cp02296c

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Periodic DFT calculations have been performed on molybdenum(VI) oxide species supported on the hydroxylated amorphous silica surface. The Mo grafting site has been investigated systematically for the type of silanol (geminate, vicinal, isolated or in a nest) accessible on the surface, as well as its effect on H-bond formation and stabilization, with the Mo-oxide species. Different grafting geometries, combined with different degrees of hydration of the Mo species are investigated using atomistic thermodynamics. The most stable Mo(VI) oxide species resulting from these calculations are confronted with experiment. Finally, calculated vibrational frequencies confirm the experimental evidence of the dominant presence of di grafted di-oxo Mo(VI) species on silica up to 700 K.

引用

页码：18253 / 18260

页数：8

共 68 条

[1] APPLICATION OF DYNAMIC PHOTOLUMINESCENCE SPECTROSCOPY TO THE STUDY OF THE ACTIVE SURFACE SITES ON SUPPORTED MO/SIO2 CATALYSTS - FEATURES OF ANCHORED AND IMPREGNATED CATALYSTS [J].