Ruthenium(0) nanoparticles supported on magnetic silica coated cobalt ferrite: Reusable catalyst in hydrogen generation from the hydrolysis of ammonia-borane

2014-11-15
Akbayrak, Serdar
KAYA, MURAT
Volkan, Mürvet
Özkar, Saim
Ruthenium(0) nanoparticles supported on magnetic silica-coated cobalt ferrite (Ru(0)/SiO2-CoFe2O4) were in situ generated from the reduction of Ru3+/SiO2-CoFe2O4 during the catalytic hydrolysis of ammonia-borane (AB). Ruthenium(III) ions were impregnated on SiO2-CoFe2O4 from the aqueous solution of ruthenium(III) chloride and then reduced by AB at room temperature yielding Ru(0)/SiO2-CoFe2O4 which were isolated from the reaction solution by using a permanent magnet and characterized by ICP-OES, XRD, TEM, TEM-EDX and XPS techniques. The resulting magnetically isolable Ru(0)/SiO2-CoFe2O4 were found to be highly reusable catalyst in hydrolysis of AB retaining 94% of their initial catalytic activity even after tenth run. Ru(0)/SiO2-CoFe2O4 provide the highest catalytic activity after the tenth use in hydrolysis of AB as compared to the other ruthenium catalysts. The work reported here also includes the formation kinetics of ruthenium(0) nanoparticles. The evaluation of rate constants for the nucleation and autocatalytic surface growth of ruthenium(0) nanoparticles at various temperatures provides the estimation of activation energy for both reactions; E-a = 116 +/- 7 kJ/mol for the nucleation and E-a = 51 +/- 2 kJ/mol for the autocatalytic surface growth of ruthenium(0) nanoparticles. The report also includes the activation energy of the catalytic hydrogen generation from the hydrolysis of AB (E-a = 45 +/- 2 kJ/mol) determined from the evaluation of temperature dependent kinetic data and the effect of catalyst concentration on the rate of hydrolysis of AB.
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL

Suggestions

Palladium(0) nanoparticles supported on silica-coated cobalt ferrite: A highly active, magnetically isolable and reusable catalyst for hydrolytic dehydrogenation of ammonia borane
Akbayrak, Serdar; KAYA, MURAT; Volkan, Mürvet; Özkar, Saim (Elsevier BV, 2014-04-05)
Palladium(0) nanoparticles supported on silica-coated cobalt ferrite (Pd(0)/SiO2-CoFe2O4) were in situ generated during the hydrolysis of ammonia borane, isolated from the reaction solution by using a permanent magnet and characterized by ICP-OES, XRD, TEM, TEM-EDX, XPS and the N-2 adsorption-desorption techniques. All the results reveal that well dispersed palladium(0) nanoparticles were successfully supported on silica coated cobalt ferrite and the resulting Pd(0)/SiO2-CoFe2O4 are highly active, magnetica...
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
Akbayrak, Serdar; Özkar, Saim (Elsevier BV, 2016-12-01)
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 generatio...
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...
Ruthenium(0) nanoparticles supported on xonotlite nanowire: a long-lived catalyst for hydrolytic dehydrogenation of ammonia-borane
Akbayrak, Serdar; Özkar, Saim (Royal Society of Chemistry (RSC), 2014-01-01)
Ruthenium(0) nanoparticles supported on xonotlite nanowire (Ru(0)@X-NW) were prepared by the ion exchange of Ru3+ 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 were characterized by a combination of advanced analytical techniques. The results show that (i) highly dispersed ruthenium(0) nanoparticles of 4.4 +/- 0.4 nm size were formed on the surface of xonotlite nanowire, (ii) Ru(0)@X-NW show hi...
Bosonic helium clusters doped by alkali metal cations: interaction forces and analysis of their most stable structures
Marinetti, F.; Coccia, E.; Bodo, E.; Gianturco, F. A.; Yurtsever, E.; Yurtsever, M.; Yıldırım, Erol (Springer Science and Business Media LLC, 2007-07-01)
Ab initio potentials are computed for alkali metal cationic partners interacting with He-4 and an overall many-body potential is constructed for each of the ionic dopants in helium clusters. The structures are then obtained via a genetic algorithm approach and results compared with Basin-Hopping Monte Carlo simulations. The classical arrangements are analyzed and quantum effects discussed in comparison with what has been found with Diffusion Monte Carlo calculations. Further corrections to the classical pic...
Citation Formats
S. Akbayrak, M. KAYA, M. Volkan, and S. Özkar, “Ruthenium(0) nanoparticles supported on magnetic silica coated cobalt ferrite: Reusable catalyst in hydrogen generation from the hydrolysis of ammonia-borane,” JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL, pp. 253–261, 2014, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42382.