Monodisperse nickel nanoparticles supported on SiO 2 as an effective catalyst for the hydrolysis of ammonia-borane

Nano Research (Impact Factor: 7.01). 09/2010; 3(9):676-684. DOI: 10.1007/s12274-010-0031-7


Monodisperse Ni nanoparticles (NPs) have been synthesized by the reduction of nickel(II) acetylacetonate with the borane-tributylamine
complex in a mixture of oleylamine and oleic acid. These Ni NPs are an active catalyst for the hydrolysis of the ammonia-borane
(AB, H3N·BH3) complex under ambient conditions and their activities are dependent on the chemical nature of the oxide support that they
were deposited on. Among various oxides (SiO2, Al2O3, and CeO2) tested, SiO2 was found to enhance Ni NP catalytic activity due to the etching of the 3.2 nm Ni NPs giving Ni(II) ions and the subsequent
reduction of Ni(II) that led to the formation of 1.6 nm Ni NPs on the SiO2 surface. The kinetics of the hydrolysis of AB catalyzed by Ni/SiO2 was shown to be dependent on catalyst and substrate concentration as well as temperature. The Ni/SiO2 catalyst has a turnover frequency (TOF) of 13.2 mol H2·(mol Ni)−1 · min−1—the best ever reported for the hydrolysis of AB using a nickel catalyst, an activation energy of 34 kJ/mol ± 2 kJ/mol and
a total turnover number of 15,400 in the hydrolysis of AB. It is a promising candidate to replace noble metals for catalyzing
AB hydrolysis and for hydrogen generation under ambient conditions.

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Available from: Saim Özkar, Jun 06, 2014
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    • "ScienceDirect journal h ome page: te/he hydrides, Sodium Borohydride (NaBH 4 ) has gained much attention due to its environmentally benevolent nature, high Hydrogen content (10.8 wt%), easy availability and acceptable Hydrogen generation rate even at low temperature using low cost catalyst [6]. Schlesinger et al. [7] established that Hydrolysis of 1 atom of NaBH 4 produces 4 atoms of Hydrogen gas and watersoluble Sodium meta borate (NaBO 2 ), in the presence of appropriate catalyst according to the following stoichiometric equation: "
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    ABSTRACT: A highly active and stable bimetallic nano-hybrid catalyst Graphene-Cobalt-Platinum (G-Co-Pt) is proposed for the enhanced and cost effective generation of hydrogen from Sodium Borohydride. Three different nano-hybrid catalysts namely Graphene-Cobalt (G-Co), Graphene-Platinum (G-Pt) and Graphene-Cobalt-Platinum (G-Co-Pt) are synthesized, characterized using XRD, FTIR, SEM, HRTEM, EDAX and Cyclic voltammetry (CV) analysis and tested for hydrogen generation. The activity and stability of the catalysts are analyzed by estimating the turnover frequency (TOF), the electrochemically active surface area (ECSA), the percentage decay of current density over ten cycles of CV and the decay in the rate of hydrogen generation with the age of catalyst. Among the three catalysts G-Co-Pt exhibits the highest catalytic activity (TOF = 107 min(-1), ECSA = 75.32 m(2)/gm) and stability. The evaluated value of activation energy of the catalytic hydrolysis using G-Co-Pt is 16 +/- 2 kJ mol(-1). Copyright
    International Journal of Hydrogen Energy 07/2014; 39(22):11566–11577. DOI:10.1016/j.ijhydene.2014.05.131 · 3.31 Impact Factor
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    • "In contrast, the amount of hydrogen evolution in the presence of hollow silicaenickel composite spheres is lower than both the ideal amount of hydrogen evolution estimated from reactions (2) and (3), indicating that the hollow silicaenickel composite spheres show no activity for hydrolysis of NH 3 BH 3 . On the other hand, the hydrogen production rate in the presence of titaniaenickel composite spheres is slightly lower than that in the presence of nickel-based composite spheres previously reported [18] [21] [25] [26] [28] [29], however, it is possible for the titaniae nickel composite spheres to improve the catalytic activity with controlling the particle size, the wall thickness, or the pore size in wall or hollow space. The as-prepared hollow metal oxideenickel composite spheres were characterized by using FTIR spectroscopic methods to confirm that the difference in the catalytic activity depends on the amount of residual PS templates. "
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    The Journal of Physical Chemistry C 11/2010; 114(49):20974. DOI:10.1021/jp105490g · 4.77 Impact Factor
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