PREPARATION AND CHARACTERIZATION OF CARBONACEOUS MATERIALS INCORPORATED WITH ORGANOMETALLIC COMPOUNDS FOR HYDROGEN STORAGE

Abstract

Preparation and Characterization of Carbonaceous materials incorporated with organometallic compounds for hydrogen storage" Carbonaceous materials are so chemically stable and have high thermal/electric conductivity, good strength and elasticity. In 21St century, carbon materials will be focused as one of promising materials for hydrogen storage. The surfaces of carbon have high energy density, so it is easy to modify for introducing some hydrogen-friendly functional groups and the porosity of carbonaceous materials can also be advantageous in hydrogen storage. Thus, the present research work is aimed to focus the possibilities of various surface treatment techniques on several porous carbonaceous materials, such as charcoal, Graphite, Carbon Nanotubes and MOFs. Some metals, such as Ti, Zn and V were introduced on the surfaces of the carbonaceous materials in order to gain optimal hydrogen storage capacity. Charcoal and graphite have been chosen as adsorbents for metal like titanium (Ti). The amount of metal incorporated in charcoal/graphite has been measured by AAS analysis technique and FESEM analysis technique and also the incorporated metal in charcoal/graphite has been confirmed by X-ray diffraction analysis. UV-visible spectra revealed the presence of organometallic compound. The AAS results revealed that maximum adsorption of titanium in charcoal was with 2% titanium n-butoxide but in graphite with 4 % titanium n-butoxide and in case of titanium di isopropoxide bis (2,4-pentanedionate) it was maximum with 2 wt% in both charcoal and graphite. The FE-SEM showed the maximum adsorption with 2% titanium n-butoxide in charcoal at calcinations temperaturelOO °C, with 4 wt% in graphite at temperature 100 °C and in case of titanium di isopropoxide bis (2,4-pentanedionate) maximum adsorption with 2 wt% at calcinations temperature 80 °C in both charcoal and graphite, equilibration time of 20-24 h was used. The comparison plot of FE-SEM results revealed that in both cases [titanium n-butoxide and titanium di isopropoxide bis (2,4-pentanedionate)] maximum adsorption was with graphite. It was investigated that the xlPage maximum adsorption of metals (Zn and V) occurs on charcoal, when 4 wt% of zinc-2,4- pentanedionate at 150 °C and equilibration time of 20-24 h and 4 wt% of vanadium-2,4- pentanedionate at 100 °C, equilibration time of 20-24 h was used. Hydrogen adsorption in different carbonaceous materials was investigated at 77.4K and low pressure up to 1 bar. The highest hydrogen uptake obtained was 1.45 wt% (164.5 cm3 (STP) /g at P/Po = 1.0) for carbonaceous material incorporated with 4 wt% of zinc 2,4- pentanedionate. xiIPage