MOF-GO Hybrid Nanocomposite Adsorbents for Methane Storage

In this study, the storage of methane in nanocomposite adsorbents comprising metal–organic framework (MOF) and graphene oxide (GO) was investigated. Three different sets of MOF-GO nanocomposites comprising HKUST-1 and pristine GO, reduced GO (rGO), and carboxyl-functionalized GO (fGO) were developed by the solvothermal method, and their methane storage characteristics were assessed through high-pressure methane adsorption measurements. The formation of MOF-GO nanocomposites was confirmed by XRD, FTIR, XPS, SEM, and TEM. All three types of nanocomposites exhibited higher surface area and porosity than the pristine MOF. Our results indicated that MOF@rGO nanocomposite with 10 wt % rGO exhibited the best performance with a methane deliverable capacity of 193 cm3(STP)/cm3 in the pressure range of 5.8–65 bar and at room temperature which was approximately 30% higher than that of pristine HKUST-1 with deliverable capacity of 149 cm3(STP)/cm3. Moreover, the methane deliverable capacity of MOF@GO and MOF@fGO were found to be 181 and 162 cm3(STP)/cm3, respectively. The findings of this study demonstrate the synergistic effect of graphene oxide on methane storage performance of MOF-GO nanocomposites.