Influence of the method of synthesis on hydrogen adsorption properties of mesoporous binary B2O3/Al2O3 gel systems

Three series of binary oxide systems B2O3/Al2O3 were prepared and the effect of alumina on dispersion of boron (B2O3) component was investigated. The aim of the study was to achieve a maximum dispersion of B2O3 in the Al2O3 a gel matrix that would lead to increased sorption capacity on boron oxide. Many attempts were made to establish the preparation conditions that would lead to a maximum dispersion of B2O3 in the Al2O3 gel matrix needed to increase the hydrogen sorption capacity on boron oxide. The systems were characterized by X-ray diffraction, SEM, TEM and low temperature nitrogen adsorption. Hydrogen adsorption was tested in the volumetric system. Results of the study showed that the amount of hydrogen adsorbed on B2O3 depended not only on the surface area of the system but also on the separation of B2O3 domains in Al2O3 gel network. Irrespective of the method of synthesis of the binary oxide system, the dispersion of B2O3 phase reflected in the amount of hydrogen adsorbed was the highest for the systems of the lowest B/Al molar ratios studied, i.e. for B/Al = 0.25. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.