The Targeted Synthesis of Single Site Vanadyl Species on the Surface and in the Framework of Silicate Building Block Materials

Journal Article · Sat Dec 31 04:00:00 EST 2011 · Catalysis Today

DOI:https://doi.org/10.1016/j.cattod.2010.06.029· OSTI ID:1042186

Lee, M; Jiao, J; Mayes, R; Hagaman, E; Barnes, C

A new synthetic methodology for the targeted preparation of single site, atomically dispersed vanadyl groups in silicate matrices is described. This methodology requires functionalized silicate building blocks Si{sub 8}O{sub 20}(OSnMe{sub 3}){sub 8} that become linked together through vanadyl ({triple_bond}V=O) groups in the matrix. A sequential addition strategy is illustrated which allows the targeting of specific connectivities for the vanadyl group to the silicate building block matrix (i.e. the number of V-O-Si bonds linking the vanadyl unit). Silicate matrices containing exclusively 3-connected (OV(OSi{sub cube}){sub 3}), 2-connected (OV(OR)(OSi{sub cube}){sub 2}) or 1-connected (OVCl{sub 2}(OSi{sub cube})) vanadyl sites are described and characterized via a wide variety spectroscopic and physical techniques (gravimetric analysis, EXAFS, AA and solid state NMR ({sup 51}V, {sup 29}Si, and {sup 17}O)). We demonstrate how the combination of gravimetric, solid state NMR (SSNMR) and EXAFS data can be used to uniquely define the vanadyl sites in these matrices. Furthermore, the use of {sup 17}O SSNMR (1D and MQMAS) is illustrated as an indirect spectroscopic probe to follow changes in the ligands bound to vanadium atom within the vanadyl groups in these matrices.

• Research Organization: BROOKHAVEN NATIONAL LABORATORY (BNL)
• Sponsoring Organization: USDOE SC OFFICE OF SCIENCE (SC)
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1042186
• Report Number(s): BNL--97864-2012-JA
• Journal Information: Catalysis Today, Journal Name: Catalysis Today Journal Issue: 1 Vol. 160; ISSN 0920-5861; ISSN CATTEA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ATOMS
CATALYSTS
MATRICES
PROBES
SILICA
SILICATES
SYNTHESIS
VANADIUM