INTRAZEOLITE NONSTOICHIOMETRIC TUNGSTEN-OXIDES N[WO3-X]-NA56Y(0-LESS-THAN-N-LESS-THAN-OR-EQUAL-TO-32, 0-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-1)

Date

1992-11-01

Author

OZIN, GA
PROKOPOWICZ, RA
Özkar, Saim

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

149
views

0
downloads

The photooxidation of alpha-cage encapsulated n[W(CO)6]-Na56Y, where 0 hv n[WO3]-Na56Y + 6nCO2 Following photooxidation, half of the alpha-cage void volume in the Na56Y host is freed so that subsequent precursor (saturation level) impregnations/photooxidations can be carried out in a stepwise fashion, proceeding as n = 16, 24, 28, 30, ..., 32 per unit cell. Thermal vacuum treatment of these materials proceeds in two well-defined steps around 300 and 400-degrees-C to yield encapsulated n[WO3-x]-Na56Y materials having x = 0.5 and 1, respectively. This reduction process is reversible by heating in an O2 atmosphere at 300-degrees-C. The entire redox process can be summarized according to the reaction stoichiometry

Subject Keywords

Colloid and Surface Chemistry, Biochemistry, General Chemistry, Catalysis

URI

https://hdl.handle.net/11511/69995

Journal

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY

DOI

https://doi.org/10.1021/ja00049a028

Collections

Department of Chemistry, Article

Suggestions

OpenMETU
Core

INTRAZEOLITE CARBONYL(ETA-5-CYCLOPENTADIENYL)DIHYDRIDOIRIDIUM(III) (CPIR(CO)H2-M56Y, WHERE M = H, LI, NA, K, RB, AND CS) CROWFOOT, L; OZIN, GA; Özkar, Saim (American Chemical Society (ACS), 1991-03-01) Vapor-phase impregnation and thermal equilibration of CpIr(CO)H2 in dehydrated M56Y (where M = H, Li, Na, K, Rb, and Cs) yields samples in which the guest displays two main anchoring modes. In Li56Y and Na56Y, a CpIrH2(CO)...M+ interaction is favored (type I), whereas in K56Y, Rb56Y, and Cs56Y the preferred-binding geometry involves CpIr(CO)H2...M+ (type II). The topology, spacial requirements, and ionic potential of the site II M+ cations appear to be mutually responsible for "lock-and-key" anchoring ef...
INTRAZEOLITE METAL-CARBONYL TOPOTAXY - A COMPREHENSIVE STRUCTURAL AND SPECTROSCOPIC STUDY OF INTRAZEOLITE GROUP-VI METAL HEXACARBONYLS AND SUBCARBONYLS Özkar, Saim; MOLLER, K; BEIN, T (American Chemical Society (ACS), 1990-12-01) This paper focuses attention on the intrazeolite anchoring, thermal decarbonylation, ligand exchange, and addition chemistry of M(CO)6-M'56Y, where M = Cr, Mo, W; M' = H, Li, Na, K, Rb, Cs. The key points to emerge from this study include the following. (i) M(CO)6-M'56Y samples have the hexacarbonylmetal(O) molecule associated with two alpha-cage extraframework cations (or Bronsted protons), via the oxygen end of two trans bonded carbonyls with a saturation loading of 2M(CO)6/alpha-cage. (ii) M(CO)6-M'56...
Cobalt Metallopeptide Electrocatalyst for the Selective Reduction of Nitrite to Ammonium Guo, Yixing; Stroka, Jesse R.; Kandemir, Banu; Dickerson, Claire E.; Bren, Kara L. (American Chemical Society (ACS), 2018-12-12) A cobalt-tripeptide complex (CoGGH) is developed as an electrocatalyst for the selective six-electron, eight-proton reduction of nitrite to ammonium in aqueous buffer near neutral pH. The onset potential for nitrite reduction occurs at -0.65 V vs Ag/AgCl (1 M KCl). Controlled potential electrolysis at -0.90 V generates ammonium with a faradaic efficiency of 90 +/- 3% and a turnover number of 3550 +/- 420 over 5.5 h. CoGGH also catalyzes the reduction of the proposed intermediates nitric oxide and hydroxylam...
GUEST HOST INTERACTIONS IN SODIUM ZEOLITE-Y - STRUCTURAL AND DYNAMIC NA-23 DOUBLE-ROTATION NMR-STUDY OF H2O, PME3, MO(CO)6, AND MO(CO)4(PME3)2 ADSORPTION IN NA56Y JELINEK, R; Özkar, Saim; PASTORE, HO; MALEK, A; OZIN, GA (American Chemical Society (ACS), 1993-01-01) Na-23 double-rotation NMR (DOR) provides site-specific structural and dynamical information on guest-host interactions within sodium zeolite Y pores. Quantitative adsorption of H2O, PMe3, and Mo(CO)6 guests affects both the positions and line shapes of the N-23 resonances from specific extraframework Na+ sites. The evolution of the Na-23 DOR spectra with the progressive introduction of guest molecules allows one to probe direct ''solvation'' effects involving the Na+ cations in the larger supercages, as wel...
Nanoparticle Nucleation Is Termolecular in Metal and Involves Hydrogen: Evidence for a Kinetically Effective Nucleus of Three {Ir3H2x center dot P2W15Nb3O62}(6-) in Ir(0)(n) Nanoparticle Formation From [(1,5-COD)Ir-I center dot P2W15Nb3O62](8-) Plus Dihydrogen Özkar, Saim (American Chemical Society (ACS), 2017-04-19) The nucleation process yielding Ir(0)(similar to 300) nanoparticles from (Bu4N)(5)Na-3[(1,5-COD)Ir center dot P2W15Nb3O62] (abbreviated hereafter as (COD)Ir center dot POM8-, where POM9- = the polyoxometalate, P2W15Nb3O629-) under H-2 is investigated to learn the true molecularity, and hence the associated kinetically effective nucleus (KEN), for nanoparticle formation for the first time. Recent work with this prototype transition metal nanoparticle formation system (J. Am. Chem. Soc. 2014, 136, 17601-17615...

Citation Formats

G. OZIN, R. PROKOPOWICZ, and S. Özkar, “INTRAZEOLITE NONSTOICHIOMETRIC TUNGSTEN-OXIDES N[WO3-X]-NA56Y(0-LESS-THAN-N-LESS-THAN-OR-EQUAL-TO-32, 0-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-1),” JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, pp. 8953–8963, 1992, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/69995.