Study on the copper(II)-doped MIL-101(Cr) and its performance in VOCs adsorption

The metal-organic framework (MOF) materials, MIL-101(Cr), and copper-doped MIL-101(Cr) (Cu@MIL-101(Cr)) were prepared through hydrothermal method and were used to remove volatile organic compounds (VOCs) in this study. Morphological characterization demonstrated that MIL-101(Cr) and Cu-3@MIL-101(Cr) were octahedral crystal, with specific surface area of 3367 and 2518 m2/g, respectively. The results of XRD, TG, and FTIR showed that the copper doping procedure would not alter the skeleton structure, but it would affect the crystallinity and thermal stability of MIL-101(Cr). Besides, MIL-101(Cr) and Cu-3@MIL-101(Cr) displayed good removal efficiencies on benzene sorption, and the maximum sorption capacity was 103.4 and 114.4 mg/g, respectively. In competitive adsorptions, the order of adsorption priority on Cu-3@MIL-101(Cr) was as follows: ethylbenzene > toluene > benzene. Hence, it could be concluded that MIL-101(Cr) and copper-doped MIL-101(Cr) demonstrated good performance in VOCs adsorption and showed a promising potential for large-scale applications in the removal of VOCs.