Ruthenium(0) Nanoparticles Supported on Multiwalled Carbon Nanotube As Highly Active Catalyst for Hydrogen Generation from Ammonia–Borane

Abstract

Ruthenium(0) nanoparticles supported on multiwalled carbon nanotubes (Ru(0)@MWCNT) were in situ formed during the hydrolysis of ammonia-borane (AB) and could be isolated from the reaction solution by filtration and characterized by ICP-OES, XRD, TEM, SEM, EDX, and XPS techniques. The results reveal that ruthenium(0) nanoparticles of size in the range 1.4-3.0 nm are well-dispersed on multiwalled carbon nanotubes. They were found to be highly active catalyst in hydrogen generation from the hydrolysis of AB with a turnover frequency value of 329 min⁻¹. The reusability experiments show that Ru(0)@MWCNTs are isolable and redispersible in aqueous solution; when redispersed they are still active catalyst in the hydrolysis of AB exhibiting a release of 3.0 equivalents of H₂ per mole of NH₃BH₃ and preserving 41% of the initial catalytic activity even after the fourth run of hydrolysis. The lifetime of Ru(0)@MWCNTs was measured as 26400 turnovers over 29 h in the hydrolysis of AB at 25.0 ± 0.1 °C before deactivation. The work reported here also includes the kinetic studies depending on the temperature to determine the activation energy of the reaction (E(a) = 33 ± 2 kJ/mol) and the effect of catalyst concentration on the rate of the catalytic hydrolysis of AB, respectively.

In situ facile synthesis of Rh nanoparticles supported on carbon nanotubes as highly active catalysts for H2 generation from NH3BH3 hydrolysis

“…These results reveal that the characteristic diffraction peaks of CNTs has no change before and after the acid treatment, indicating that the CNTs were not severely damaged by refluxing in the mixture of HNO 3 /H 2 SO 4 . A similar phenomenon has also been reported by € Ozkar and co-workers [32]. The acid treatment for pristine CNTs is applied to introduce more defects and oxygen groups (Fig.…”

Facile reduction of graphene oxide at room temperature by ammonia borane via salting out effect

“…Generally speaking, thermal dehydrogenation process requires high temperature and power consumption. In contrast, NH 3 BH 3 can release hydrogen via hydrolysis reaction in the presence of a suitable catalyst (Ru [39], Pd [40], Co [41]) at room temperature.…”

Preparation, structure and adsorption properties of synthesized multiwall carbon nanotubes for highly effective removal of maxilon blue dye

“…The pattern indicates the existence of the graphite peak at 26.5 as assigned earlier [21]. As shown, the strongest diffraction peak at 26.5 o , peaks with medium intensity at 44.6 o , and weak peaks at 54.2 o can be well indexed as the (002), (100), and (004) reflections of graphite, respectively [22,23]. Similar findings have been reported by other researchers [24][25][26].…”