Nanoclusters of Vanadium Oxide Included in Hybrid Nanostructured Materials Use as Hydrogen Storage Material

JULIANA MARIA JUAREZ; MARCOS B. GÓMEZ COSTA; M. LAURA MARTINEZ, ; OSCAR ANUNZIATA

Cancún

Congreso; XXVII International Material Research Congress (IMRC 2018); 2018

IMRC

In this work we studied the influence of the incorporation of vanadium oxide nanoparticles inside the channels of two different supports such as the mesoporous silicate SBA-15 and into the mesoporous carbon CMK-3. This research includes synthesis of the mesoporous silicate and synthesis of CMK-3 by nanocasting strategy, incorporation of the vanadium nanoclusters by wetness impregnation, characterization of these nanomaterials by XRD, N2 adsorption, XPS, TPR and UV-Vis, TEM, and study of the improvement in hydrogen adsorption. This material is promising in hydrogen adsorption and storage application for energy harvesting. The materials with vanadium oxide nanoclusters (VxOy-SBA-15 and VxOy-CMK-3) were successfully synthesized and characterized by X-ray diffraction, Textural properties, UV?Vis?DRS, X-Ray Photoelectron Spectroscopy, Temperature Programmed Reduction and Transmission Electron Microscopy analyses. VxOy-SBA-15 and VxOy-CMK-3 improved significantly the H2 storage behavior (1.33 wt.% and 3.43 wt.% at 77K and 10 bar) compared with their respective supports SBA-15 and CMK-3. The hydrogen sorption onto SBA-15 was smaller than vanadium oxide samples in a close factor by two; when vanadium was added, hydrogen uptake increased. A similar behavior was found with carbon materials; yet, the amount of H2 adsorption molecules was more important than that found in siliceous materials. V2O5 nanoclusters increased the capacity of hydrogen adsorption in pristine materials. The importance lies in the V5+ metal cation is the main component that increased the adsorption capacity of these materials. Supposing that weakly orbital interactions occur between H2 and the metal nanocluster, physisorption is the main interaction, all cases have the potential to uptake H2 weakly as physisorption process and the last interaction achieves sufficiently strong energies to store more hydrogen to reach the level adsorption in VxOy-CMK-3. In addition, no hydrogen chemisorption was detected. The materials synthesized are promising in hydrogen uptake by weak link forces (physisorption). A mechanism of hydrogen adsorption was proposed and V+5 cation roll in hydrogen uptake was discussed.