Facile and cost-efficient synthesis of highly efficient CO2 adsorbents: a pathway towards a green environment

The synthesis of highly efficient CO2 adsorbent derived from MOF coupled with graphene oxide, HKUST-1@GrO, is proposed at the room temperature to achieve the most desirability form an eco-environmental perspective. The modified Hummers method coupled with an ultra-fast MOF formation approach were explored to synthesis the superior CO2 adsorbent, i.e. HKUST-1@GrO. Then, the structure of adsorbent was deeply characterized by the application of different analyses including Fourier-Transform Infrared (FTIR) Spectroscopy, X-ray Diffraction (XRD), Brunauer–Emmett–Teller (BET), and Scanning Electron Microscopy (SEM). The optimization of CO2 adsorption was carried out under a broad range of temperatures (283–293 K) and pressures (1–10 bars). The N2 adsorption/desorption isotherms analysis indicated that loading of graphene oxide (3 wt%) on HKUST-1 increases its specific surface area from 1032 to 1354 m2/g. The maximum adsorption capacity of CO2 by HKUST-1@GrO composite at 283 K and 10 bars was evaluated equal to 12.44 mmol/g. Thermodynamic studies elucidated that the dominant CO2 adsorption was taken place as spontaneous, physisorption, and exothermic.