caa a22 4500 445388137 CHVBK 20180317143038.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s11144-011-0306-3 doi (NATIONALLICENCE)springer-10.1007/s11144-011-0306-3 Effect of stabilizer type on the activity and stability of water-dispersible cobalt(0) nanocluster catalysts in hydrogen generation from the hydrolysis of sodium borohydride [Elektronische Daten] [Önder Metin, Ebru Koçak, Saim Özkar] Hydrogen phosphate (HPO4 2−) or poly(acrylic acid) (PAA) stabilized cobalt(0) nanoclusters were in situ generated from the reduction of cobalt(II) chloride during the catalytic hydrolysis of sodium borohydride (NaBH4) in the presence of stabilizers, HPO4 2− or PAA. Cobalt(0) nanoclusters stabilized by HPO4 2− or PAA were characterized by using UV-Visible spectroscopy, TEM, XPS and FT-IR techniques. They were employed as catalysts in the hydrolysis of NaBH4 to examine the effect of stabilizer type on their catalytic activity and stability. Detailed reaction kinetics of the hydrolysis of NaBH4 in the presence of both catalysts was studied depending on catalyst concentration, substrate concentration and temperature. PAA stabilized cobalt(0) nanoclusters provided higher total turnover number (TTON=6,600) than that of HPO4 2− stabilized cobalt(0) nanoclusters (1,285 turnovers). However, the HPO4 2− stabilized cobalt(0) nanoclusters provided a lower activation energy (E a=53±2kJmol−1) than the PAA stabilized cobalt(0) nanoclusters (E a=58±2kJmol−1) for the hydrolysis of NaBH4. The use of two types of stabilizers in the preparation of the same metal(0) nanoclusters following the same methodology enables us to compare the electrostatic and steric stabilization in terms of the catalytic activity and stability of metal(0) nanoclusters. Akadémiai Kiadó, Budapest, Hungary, 2011 Cobalt nanoclusters nationallicence Hydrogen phosphate nationallicence Poly(acrylic acid) nationallicence Hydrogen generation nationallicence Hydrolysis of sodium borohydride nationallicence Kinetics nationallicence Metin Önder Department of Chemistry, Middle East Technical University, 06531, Ankara, Turkey aut Koçak Ebru Department of Chemistry, Middle East Technical University, 06531, Ankara, Turkey aut Özkar Saim Department of Chemistry, Middle East Technical University, 06531, Ankara, Turkey aut Reaction Kinetics, Mechanisms and Catalysis Springer Netherlands 103/2(2011-08-01), 325-340 1878-5190 103:2<325 2011 103 11144 https://doi.org/10.1007/s11144-011-0306-3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11144-011-0306-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Metin Önder Department of Chemistry, Middle East Technical University, 06531, Ankara, Turkey aut NATIONALLICENCE 700 1- Koçak Ebru Department of Chemistry, Middle East Technical University, 06531, Ankara, Turkey aut NATIONALLICENCE 700 1- Özkar Saim Department of Chemistry, Middle East Technical University, 06531, Ankara, Turkey aut NATIONALLICENCE 773 0- Reaction Kinetics, Mechanisms and Catalysis Springer Netherlands 103/2(2011-08-01), 325-340 1878-5190 103:2<325 2011 103 11144 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer