Polymer-immobilized palladium supported on TiO2 (Pd-PVB-TiO2) as highly active and reusable catalyst for hydrogen generation from the hydrolysis of unstirred ammonia-borane solution

Rakap, Murat
Kalu, Egwu Eric
Özkar, Saim
Herein we report the preparation, characterization and the catalytic use of the polymer-immobilized palladium catalyst supported on TiO2 (Pd-PVB-TiO2) in the hydrolysis of unstirred ammonia-borane solution. The polymer-immobilized palladium catalyst is stable enough to be isolated as solid materials and characterized by XRD, SM, and EDX. The immobilized palladium catalyst supported on TiO2 is found highly active, isolable, and reusable in the hydrolysis of unstirred ammonia-borane even at low concentrations and temperature. The work reported here also includes the full experimental details for the collection of a wealth of kinetic data to determine the activation energy (E-a = 55.9 kJ/mol) and the effects of catalyst and substrate concentration on the rate for the hydrolysis of unstirred ammonia-borane solution. Maximum H-2 generation rate of similar to 642 mL H-2 min(-1) (g Pd)(-1) and similar to 4367 mL H-2 min(-1) (g Pd)(-1) was measured by the hydrolysis of AB at 25 degrees C and 55 +/- 0.5 degrees C, respectively. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.


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Rh3+ ions are first impregnated on Group 4 metal oxides (TiO2, ZrO2, HfO2) in aqueous solution and, then reduced with aqueous solution of NaBH4 to form rhodium(0) nanoparticles (NPs) on the oxide surface. The analyses reveal that Rh(0) NPs are highly dispersed on the surface of TiO2, ZrO2, HfO2. Rh-0/MO2 (M: Ti, Zr, Hf) NPs have high activity and reusability in releasing H-2 from the hydrolysis of ammonia borane with an initial turnover frequency of 643, 198, and 188 min(-1), respectively, at 25.0 +/- 0.1 d...
Citation Formats
M. Rakap, E. E. Kalu, and S. Özkar, “Polymer-immobilized palladium supported on TiO2 (Pd-PVB-TiO2) as highly active and reusable catalyst for hydrogen generation from the hydrolysis of unstirred ammonia-borane solution,” INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, pp. 1448–1455, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/62718.