Group 4 oxides supported Rhodium(0) catalysts in hydrolytic dehydrogenation of ammonia borane

Tonbul, Yalcin
Akbayrak, Serdar
Özkar, Saim
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 degrees C. The reusability of Rh-0/ZrO2 and Rh-0/HfO2 catalysts is higher than that of the Rh-0/TiO2 catalyst. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.


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Sencanli, Selin; Karahan, Senem; Özkar, Saim (Elsevier BV, 2013-11-13)
When hydrazine borane is added to the solution of nickel(II) chloride and poly(4-styrenesulfonic acid-co-maleic acid), PSSMA, both reduction of nickel(II) ions to nickel(0) nanoparticles and hydrogen release from the hydrolysis of hydrazine borane occur concomitantly at room temperature. Using the hydrogen evolution from the hydrolysis of hydrazine borane as reporter reaction provides valuable insights to the formation kinetics of nickel(0) nanoparticles. Nickel(0) nanoparticles are in situ formed from the ...
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Water-dispersible nickel(0) nanoclusters are prepared from the reduction of nickel(II) acetylacetonate by sodium borchydride in aqueous solution and stabilized by hydrogerphosphate anion. Hydrogenphosphate-stabilized nickel(0) nanoclusters were characterized by using XPS, FT-IR, UV-Vis and NMR spectroscopic methods. As the first example of water-dispersible nickel(0) nanoclusters, they were employed as catalyst in the hydrolysis of sodium borohydride. Hydrogenphosphate-stabilized nickel(0) nanoclusters were...
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Ozhava, Derya; Özkar, Saim (Elsevier BV, 2015-09-07)
Rhodium(0) nanoparticles, supported on nanosized hydroxyapatite (Rh(0)/nanoHAP), were prepared by ion exchange of Rh+3 ions with Ca+2 ions of hydroxyapatite, followed by reduction of the resulting Rh+3/nanoHAP precatalyst during the catalytic methanolysis of ammonia borane (AB) in the presence of tetrabutylammonium dihydrogen phosphate (TBAP) at room temperature. Rh(0)/nanoHAP were characterized by a combination of advance analytical techniques including ICP-OES, XRD, TEM, EDX, XPS, ATR-IR and N-2 adsorptio...
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Gencer, Ayşenur; Surucu, Gokhan (Elsevier BV, 2019-06-07)
XNiH3 (X = Li, Na, and K) perovskite type hydrides have been studied by using Density Functional Theory (DFT) and these materials are found to be stable and synthesizable. The X-ray diffraction patterns have been obtained and they indicate that all materials have the polycrystalline structure. The electronic properties have been investigated and it has been found that these structures show metallic character. The Bader partial charge analysis has also been performed. In addition, the elastic constants have ...
Citation Formats
Y. Tonbul, S. Akbayrak, and S. Özkar, “Group 4 oxides supported Rhodium(0) catalysts in hydrolytic dehydrogenation of ammonia borane,” INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, pp. 14164–14174, 2019, Accessed: 00, 2020. [Online]. Available: