MWCNT@MIL53 (Cr) Nanoporous Composite: Synthesis, Characterization, and Methane Storage Property

In this paper, porous metal−organic frameworks (MIL-53 [CrIII (OH).{O2C-C6H4-CO2}.{HO2C-C6H4-CO2H}x]) were hydrothermally synthesized and, then, a hybrid composite of these synthesized porous metal−organic frameworks (MOF) with acid-treated multi-walled carbon nanotubes (MWCNTs) was prepared. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmet–Teller (BET), and FT-IR analysis. The X-ray diffraction patterns showed that the structure of MWCNT@MIL-53-Cr nonoporous composite was not disturbed by incorporation of MWCNT in MIL-53-Cr. N2 adsorption – desorption analysis showed that the MIL-53-Cr and MWCNT@MIL-53-Cr nanoporous composite had BET surface areas of 1500m^2.g^-1 and 1347m^2.g^-1, respectively. These materials were developed as adsorbents for methane storage at room temperature. The analysis showed about 50% increase in methane storage capacity (from 7.1 to 10.8 mmol.g^-1 at 298K and 35bar) for MWCNT@MIL-53-Cr composite. The increment in the CH4 adsorption capacity of MWCNT@MIL-53-Cr nanoporous composite is attributed to the increase in micropore volume of MIL-53-Cr by MWCNT incorporation.