Desarrollo, Producción e Innovación en la Investigación científica
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Item Direct synthesis and characterization of mesoporous carbon CMK-3 modified with zirconia applied in energy storage(2020) Venosta, Lisandro F.; Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.In this work, we report the synthesis and characterization of the nanostructured carbon material (CMK- 3) modified with zirconium oxide synthesized by a new direct synthesis technique. The aim of this new synthesis method is to avoid the use of inorganic siliceous template (SBA-15), which leads to a shorter and cheaper way to obtain mesoporous carbon, and at the same time incorporate into the framework Zirconium atoms. Zirconium oxide dispersed in carbon materials (Zr-CMK-3) were successfully synthesized and characterized by X-ray diffraction, textural properties, UV-Vis-DRS, XPS, and transmission electron microscopy analysis. This material is promising in the application of hydrogen adsorption for energy storage. Zr-CMK-3 material significantly improved H2 storage behavior (4.6% by weight at 77 K and 10 bar) compared to CMK-3 support. The synthesized material is promising in the absorption of hydrogen by weak bonding forces (physisorption). A hydrogen adsorption mechanism was proposed and the role of the Zr+4 cation in hydrogen absorption was discussed. The activity of the samples to the adsorption of hydrogen molecules is attributed to the improved dispersion of the zirconium oxide, as well as the appropriate use of support, which can probably disperse the zirconium on its large surface area, allowing a great dispersion of the zirconium. The Zr+4 cation is an active species to absorb and store hydrogen through a physisorption process and the carbon plays an important role in the dispersion and size of metal particles. A hydrogen storage mechanism on the active surface of the ZrO2 clusters was proposed. First layer of hydrogen molecules can react with the metal cation through a dihydrogen complex (Kubas interaction) [1]. The second layer of hydrogen molecules adsorbed around the metal oxide clusters is due to dipole-like interactions, this is because the metal particle induces dipole forces on the hydrogen molecule. The other layers could also interact by dipole forces; however, the interaction force decreases as the distance to the surface increases. The interaction of the induced dipole in a second layer adsorbs more hydrogen molecules because the strong interaction of the metal particles takes up dipole-induced forces on the hydrogen molecules. The upper layers could interact with the metal cation by dipole-induced bonding; however, the interaction force decreases as the distance to the surface increases. The procedure for this adsorption is still under investigation and optimization. The hydrogen storage behavior in Zr-CMK-3 can be optimized by controlling the size of the metal particles, the dispersion and the nature of the support.Item Síntesis directa del carbón mesoporoso ordenado cmk-3 modificado con circonio aplicado en almacenamiento de energía(2020) Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.; Venosta, Lisandro F.En este trabajo, informamos la síntesis y caracterización del material de carbono nanoestructurado (CMK-3) modificado con óxido de circonio sintetizado por una nueva técnica de síntesis directa. Este material es prometedor en la aplicación de adsorción de hidrógeno para el almacenamiento de energía. Los materiales con óxido de circonio (Zr-CMK-3) se sintetizaron con éxito y se caracterizaron por difracción de rayos X, propiedades texturales, UV-Vis-DRS, XPS y análisis de microscopía electrónica de transmisión. El material Zr-CMK-3 mejoró significativamente el comportamiento de almacenamiento de H2 (4,6% en peso a 77 K y 10 bar) en comparación con el soporte CMK-3. El material sintetizado es prometedor en la absorción de hidrógeno por fuerzas de enlace débiles (fisisorción). Se propuso un mecanismo de adsorción de hidrógeno y se discutió el rol de catión Zr+4 en la absorción de hidrógeno.Item Novel omc by nanocasting strategy for hydrogen adsorption(2021) Juárez, Juliana M.; Gómez Costa, Marcos B.; Anunziata, Oscar A.A silica material of the SBA-15 type with ultra-large pores (20 nm) was synthesized by the sol-gel method. This silica mesoporous material was impregnated twice consecutively with an acid solution of sucrose and the organic material carbonised inside the mesopores. After dissolution of the silica framework, an ordered mesoporous carbon (OMC) with regular mesopores with mean diameter in the range of 6 nm. The specific surface area of the carbon was increased by increasing filling of the silica pores with the organic material, from 350 m2/g to 950 m2/g. The novel OMC material was successfully synthesized and characterized by X-ray diffraction, textural properties, SEM and transmission electron microscopy analyses. This novel OMC improved significantly the H2 storage behaviour (2.62 wt% at 77 K and 10 bar) compared with a similar CMK-3 (2.18 wt% at 77K and 10 bar). The synthesized material is promising for hydrogen uptake by means of weak bonding (physisorption).