Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Inverse relation between the catalytic activity and catalyst concentration for the ruthenium(0) nanoparticles supported on xonotlite nanowire in hydrogen generation from the hydrolysis of sodium borohydride
Date
2016-12-01
Author
Akbayrak, Serdar
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
173
views
0
downloads
Cite This
Ruthenium(0) nanoparticles supported on xonotlite nanowire (Ru(0)/X-NW) were prepared by the ion exchange of Rua* ions with Ca2+ ions in the lattice of xonotlite nanowire followed by their reduction with sodium borohydride in aqueous solution at room temperature. Ru(0)/X-NW show high catalytic activity and long life time in hydrogen generation from the hydrolysis of sodium borohydride with a turnover frequency value up to 305 min(-1) and a total turnover number of 63,100 mol H-2/mol Ru in hydrogen generation from the hydrolysis of sodium borohydride at 25.0 +/- 0.1 degrees C. Moreover, the catalytic activity of Ru(0)/X-NW shows an inverse dependence on the catalyst concentration. Ru(0)/X-NW at different ruthenium concentrations were characterized by high resolution transmission electron microscopy. The results reveal that Ru(0)/X-NW have tunable particle size depending on the metal concentration. An increase in the mean particle size of ruthenium(0) nanoparticles is observedwhen the metal concentration increases. The smaller particle size distribution at low ruthenium concentrations exhibits higher catalytic activity in hydrogen generation from the hydrolysis of sodium borohydride. The reaction kinetics of the catalytic hydrolysis of sodium borohydride was also studied.
Subject Keywords
Physical and Theoretical Chemistry
,
Process Chemistry and Technology
,
Catalysis
URI
https://hdl.handle.net/11511/47136
Journal
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
DOI
https://doi.org/10.1016/j.molcata.2016.09.001
Collections
Department of Chemistry, Article
Suggestions
OpenMETU
Core
Palladium(0) nanoclusters stabilized by poly(4-styrenesulfonic acid-co-maleic acid) as an effective catalyst for Suzuki-Miyaura cross-coupling reactions in water
Metin, Onder; DURAP, FEYYAZ; AYDEMİR, MURAT; Özkar, Saim (Elsevier BV, 2011-03-01)
Palladium(0) nanoclusters stabilized by poly(4-styrenesulfonic acid-co-maleic acid), PSSA-co-MA, were generated in situ during the hydrolysis of ammonia-borane (AB) from the reduction of potassium tetrachloropalladate(II) in aqueous solution at room temperature. They were isolated from the reaction solution and characterized by UV-visible electronic absorption spectroscopy, TEM, SAED and XRD techniques. The PSSA-co-MA stabilized palladium(0) nanoclusters were used as catalyst in Suzuki-Miyaura cross-couplin...
Self-sustained oscillatory behavior of NO+CH4+O-2 reaction over titania-supported Pd catalysts
OZKAN, UMIT; KUMTHEKAR, MAHESH; Karakaş, Gürkan (Elsevier BV, 1997-10-01)
Self-sustained, regular oscillations were observed in NO + CH4 + O-2 reaction over Pd/TiO2 catalysts at specific temperatures and oxygen concentrations. The oscillatory behavior was investigated combining NO reduction and methane combustion reaction studies with additional catalyst characterization experiments performed under controlled atmospheres. The catalyst was prepared using a wet impregnation technique with Pd-acetate as the precursor for palladium. A fixed-bed, flow reactor system was used to perfor...
Intrazeolite cobalt(0) nanoclusters as low-cost and reusable catalyst for hydrogen generation from the hydrolysis of sodium borohydride
Rakap, Murat; Özkar, Saim (Elsevier BV, 2009-09-07)
Intrazeolite cobalt(0) nanoclusters were prepared by ion-exchange of Co2+ ions with the extraframework Na+ ions in the zeolite-Y followed by the reduction of Co2+ ions in the supercages of zeolite-Y with sodium borohydride at room temperature. The intrazeolite cobalt(0) nanoclusters were isolated as solid materials and characterized by ICP-OES, XRD, HRTEM, SEM, XPS, Raman spectroscopy and N-2 adsorption technique. The catalytic activities of intrazeolite cobalt(0) nanoclusters in the hydrolysis reaction of ...
Nonlinear effects in proline-thiourea host-guest complex catalyzed aldol reactions in nonpolar solvents
Demir, Ayhan Sıtkı; Eymur, Serkan (Elsevier BV, 2010-03-16)
An aldol reaction catalyzed by a proline-thiourea host-guest complex in a nonpolar solvent shows excellent nonlinear effects. This proline-thiourea system has the ability to form a hydrogen-bonding network. The enantiomeric excess of proline in a solution can be significantly enhanced by its incorporation with a urea molecule into its solid racemate. This suggests a general and facile route to homochirality, which may be involved in the origin of chirality on earth.
Exceptionally thermally stable, hydrocarbon soluble Ziegler-type Ir(0)(n) nanoparticle catalysts made from [Ir(1,5-COD)(mu-O2C8H15)](2) plus AlEt3: Tests of key hypotheses for their unusual stabilization
Hamdemir, Isil K.; Özkar, Saim; Finke, Richard G. (Elsevier BV, 2013-11-01)
In recent work we showed that Ziegler-type nanoparticles made from [Ir(1,5-COD)(mu-O2C8H15)](2) plus AlEt3 are an unusually thermally stable (>= 30 min at 200 degrees C), hydrocarbon-solvent soluble, high catalytic activity nanoparticle catalyst (I.K. Hamdemir, S. Ozkar, K.-H. Yih, J.E. Mondloch, R.G. Finke, ACS Catal. 2 (2012) 632-641). As such, they are analogous to-and currently the cleanest and best characterized model system for-Ziegler-type nanoparticles made from Co or Ni precatalysts plus AlEt3 whic...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
S. Akbayrak and S. Özkar, “Inverse relation between the catalytic activity and catalyst concentration for the ruthenium(0) nanoparticles supported on xonotlite nanowire in hydrogen generation from the hydrolysis of sodium borohydride,”
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
, pp. 254–260, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47136.