Hollow ruthenium nanoparticles with small dimensions derived from Ni@Ru core@shell structure: synthesis and enhanced catalytic dehydrogenation of ammonia borane

Abstract

Hollow Ru nanoparticles with ~14 nm diameter and ~2 nm shell thickness are reported for the first time, by removal of Ni from the delicately designed Ni@Ru core@shell NPs. Such hollow Ru NPs exhibit enhanced catalytic activity in the dehydrogenation of ammonia borane with respect to solid ones.

In situ facile synthesis of ruthenium nanocluster catalyst supported on carbon black for hydrogen generation from the hydrolysis of ammonia-borane

“…The broad Ru peak suggests that the size of particles is quite small at the nanoscale, which is consistent with the particle size distribution (Fig. S1) from our TEM analysis [28,29].…”

“…1C. The peak at 2q w24 is associated with the carbon black while the strong diffraction peak at 2q w44 is attributed to the (101) plane of hexagonal close-packed phase of metallic Ru with a d-value of 2.06 Å [28,29]. The broad Ru peak suggests that the size of particles is quite small at the nanoscale, which is consistent with the particle size distribution (Fig.…”

“…For example, poly (4-styrenesulfonic acid-co-maleic acid) stabilized ruthenium(0) and palladium(0) nanoclusters [13] and laurate-stabilized ruthenium(0) nanoclusters [14] have been investigated for hydrogen generation from the hydrolysis of AB. In previous work, we reported new coreeshell structured Ni@Ru [23] and hollow Ru [28] nanoparticles supported on carbon black as a catalytic system for the hydrolysis of AB, where oleic acid and oleylamine act as surface ligands for the bimetallic nanoparticles. Although high catalytic activity was observed in all these cases, the presence of surface ligands in general leads to the decrease of catalytic activity, since a fraction of surface active sites are blocked [14].…”

“…Herein, we report the in situ synthesis of ultra-small, ligandfree Ru nanoclusters, stabilized and supported by Ketjen carbon black (Ru/C), through reduction of RuCl 3 ,nH 2 O during the hydrolysis process of AB. Ketjen carbon black was chosen as a support because it has been reported as a very good support for catalysts in the AB hydrolysis reaction [17,20,23,28]. The basic concept of this approach is to take advantage of the high surface area of carbon black and the reducibility of Ru 3þ by AB to obtain highly dispersed and stable Ru nanoclusters.…”

Semiconductor and Metallic Core–Shell Nanostructures: Synthesis and Applications in Solar Cells and Catalysis

“…[123] Recently, AB has been identified as one of the leading molecular candidates for hydrogen storage because of its outstanding physicochemical properties. [139,140] Hydrogen can be released by the hydrolysis of AB in the presence of a metal catalyst, such as Pt, Rh and NiRh alloy NPs that have been demonstrated to be among the most active ones. [141,142] Very recently, core-shell NPs have also been explored for this reaction and were found to show higher activity than corresponding single-metal NPs.…”