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Article Citation - WoS: 136Citation - Scopus: 148Palladium(0) Nanoparticles Supported on Silica-Coated Cobalt Ferrite: a Highly Active, Magnetically Isolable and Reusable Catalyst for Hydrolytic Dehydrogenation of Ammonia Borane(Elsevier, 2014) Akbayrak, Serdar; Kaya, Murat; Volkan, Murvet; Ozkar, SaimPalladium(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, magnetically isolable, and recyclable catalysts in hydrogen generation from the hydrolysis of ammonia borane with an unprecedented turnover frequency (TOF, calculated on the basis of the total amount of Pd) of 254 mol H-2 (mol Pd min)(-1) at 25 +/- 0.1 degrees C. The reusability tests reveal that Pd(0)/SiO2-CoFe2O4 are still active in the subsequent runs of hydrolysis of ammonia borane providing 100% conversion. Pd(0)/SiO2-CoFe2O4 provide the highest catalytic activity with a TOF value of 198 mol H-2 (mol Pd min)(-1) in the 10th use in hydrogen generation from the hydrolysis of ammonia borane as compared to the other palladium catalysts. The work reported here also includes the kinetic studies depending on the temperature to determine the activation energy of the reaction (E-a = 52 +/- 2 kJ/mol) and the effect of catalyst concentration on the rate of hydrolytic dehydrogenation of ammonia borane, respectively. (C) 2013 Elsevier B.V. All rights reserved.Article Citation - WoS: 37Citation - Scopus: 41Carbon Nanotube-Graphene Hybrid Supported Platinum as an Effective Catalyst for Hydrogen Generation From Hydrolysis of Ammonia Borane(Pergamon-elsevier Science Ltd, 2019) Uzundurukan, Arife; Devrim, YilserIn this study, we report the results of a kinetic study on the hydrogen (H-2) generation from the hydrolysis of ammonia borane (NH3BH3) catalyzed by Platinum supported on carbon nanotube-graphene hybrid material (Pt/CNT-G). Synthesized catalyst was characterized by TGA, XRD, CP-OES, TEM and SEM-EDX techniques. Characterization studies have shown that the CNT-G hybrid support material provides desired distribution of the Pt particles on the support material. The effect of various parameters such as catalyst loading, reaction temperature, effect of NaOH and the effect of NH3BH3 concentration are also determined. Experimental results showed that the Pt/CNT-G catalyst exhibited high catalytic activity on NH3BH3 hydrolysis reaction to release H-2. It has been found that Pt/CNT-G catalyst shows low activation energy of 35.34 kJ mol(-1) for hydrolysis reaction of NH3BH3. Pt/CNT-G catalyst also exhibited high catalytic activity with turnover frequency (TOF) of 135 (mol(H2)/mol(cat).-min). Therefore, the synthesized Pt/CNT-G catalyst is a potential candidate for enhanced H-2 generation through NH3BH3 hydrolysis. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
