Carbon supported bimetallic Ru-Co catalysts for H₂ production through NaBH₄ and NH₃ BH₃ hydrolysis

Abstract

Summary This work investigates the effect of the addition of small amounts of Ru (0.5‐1 wt%) to carbon supported Co (10 wt%) catalysts towards both NaBH4 and NH3BH3 hydrolysis for H2 production. In the sodium borohydride hydrolysis, the activity of Ru‐Co/carbon catalysts was sensibly higher than the sum of the activities of corresponding monometallic samples, whereas for the ammonia borane hydrolysis, the positive effect of Ru‐Co systems with regard to catalytic activity was less evident. The performances of Ru‐Co bimetallic catalysts correlated with the occurrence of an interaction between Ru and Co species resulting in the formation of smaller ruthenium and cobalt oxide particles with a more homogeneous dispersion on the carbon support. It was proposed that Ru°, formed during the reduction step of the Ru‐Co catalysts, favors the H2 activation, thus enhancing the reduction degree of the cobalt precursor and the number of Co nucleation centers. A subsequent reduction of cobalt and ruthenium species also occurs in the hydride reaction medium, and therefore the state of the catalyst before the catalytic experiment determines the state of the active phase formed in situ. The different relative reactivity of the Ru and Co active species towards the two investigated reactions accounted for the different behavior towards NaBH4 and NH3BH3 hydrolysis.

Ru–Pd Bimetallic Catalysts Supported on CeO2-MnOX Oxides as Efficient Systems for H2 Purification through CO Preferential Oxidation

“…The deconvolution procedure ( Figure S1A) led to the distinction of three different components at around 199 °C, 246 °C and 314 °C, respectively. Reasonably, considering also the TPR quantification reported in Table S1, the low temperature feature at 200 °C can be attributed to the reduction of the Ru precursor shifted at higher temperature with respect to Ru/CeO2 due to a stronger metal-support interaction [37]; the signal at around 315 °C can be assigned to the reduction of ceria surface oxygen interacting with ruthenium and manganese oxide; and the feature at 245 °C is probably due to the reduction of manganese oxide species (Mn2O3 → Mn3O4) [36] overlapping with the reduction of dispersed RuOX particles on the surface of CeO2-MnOx. The Pd/CeO2-MnOx catalyst A quite sharp reduction peak at 435 • C characterizes the TPR profile of the CeO 2 -MnO x catalyst.…”

An efficient bio‐inspired catalytic tool for hydrogen release at room temperature from a stable borohydride solution

“…In the open literature, many studies propose interesting highly efficient catalysts. [14][15][16] However, generally these catalysts are under powder form and are not compatible with process intensification (eg, continuous process). The main drawbacks with catalytic powders include high pressure drop, low catalyst recyclability and process engineering.…”

Highly efficient CoB catalyst using a support material based on Spirulina microalgal strain treated with ZnCl 2 for hydrogen generation via sodium borohydride methanolysis

“…[1][2][3][4] Sodium borohydride (SB), which has been reported in various hydrogen storage methods, has been considered the most promising for a solid hydrogen storage material due to its advantages such as high hydrogen content, high stability, flammability, and other hydrogen storage materials with a 10.8% by weight of hydrogen. 5,6 Because of the very slow hydrolysis of SB in aqueous solution without the presence of a catalyst, it is important to synthesize highly catalytic activating catalysts and use them in the hydrolysis of SB. Various metals for the hydrolysis of SB have used as well-known catalysts.…”