A novel bimetallic MIL-101(Cr, Mg) with high CO2 adsorption capacity and CO2/N2 selectivity

作者：Zhou, Zhenyu; Mei, Liang; Ma, Chen; Xu, Feng; Xiao, Jing^*; Xia, Qibin; Li, Zhong^*

来源：Chemical Engineering Science, 2016, 147: 109-117.

DOI：10.1016/j.ces.2016.03.035

• MIL-101(Cr, Mg)
• CO2/N-2 separation
• Adsorptionselectivity

A novel bimetallic MIL-101(Cr, Mg) was successfully synthesized for the first time by doping Mg during the solvothermal synthesis of MIL-101(Cr), and then characterized. The doped magnesium was homogeneously dispersed in the crystals of MIL-101(Cr, Mg). The magnesium ions had successfully coordinated with the carboxylic group in BDC through Mg-O. The synthesized MIL-101(Cr, Mg) remained excellent moisture-stability after exposed to humid air with 90% relative humidity for 30 days. Importantly, Mg doping not only made MIL-101(Cr, Mg) had higher surface area than MIL-101(Cr), but also created new and strong adsorptive sites for CO2 confirmed by TPD experiments. As a result, CO2 adsorption capacity of MIL-101(Cr, Mg) was significantly improved, and reached 3.28 mmol/g at 298 K and 1 bar, having an increase of 40% in comparison with MIL-101(Cr). More importantly, the CO2/N-2 adsorption selectivity of MIL-101(Cr, Mg) was significantly enhanced up to 86 at 100 kPa, being similar to 4 times of that of MIL-101(Cr). The strategy of doping metal ions can be an effective way to improve the adsorption performance of MOFs.

• 出版日期2016-6-22
• 单位华南理工大学