Gas sorption properties and kinetics of porous bismuth-based metal-organic frameworks and the selective CO2 and SF6 sorption on a new bismuth trimesate-based structure UU-200

Bismuth-based metal-organic frameworks (Bi-MOFs) such as bismuth subgallate are important for applications ranging from medicine to gas separation and catalysis. Due to the porous nature of such Bi-MOFs, it would be valuable to understand their gas sorption and separation properties. Here, we present the gas sorption properties of three microporous Bi-MOFs, namely, CAU-17, CAU-33, and SU-101, along with a new trimesate-based structure, UU-200. We perform a detailed analysis of the sorption properties and kinetics of these Bi-MOFs. UU-200 shows good uptake capacities for CO2 (45.81 cm3 g−1 STP) and SF6 (24.69 cm3 g−1 STP) with CO2/N2 and SF6/N2 selectivities over 35 and 44, respectively at 293 K, 100 kPa. The structure of UU-200 is investigated using continuous rotation electron diffraction and is found to be a 3D porous framework containing pores with a diameter of 3.4–3.5 Å. Bi-MOFs as a group of relatively under-investigated types of MOFs have interesting sorption properties that render them promising for greenhouse gas adsorbents with good gas uptake capacities and high selectivities.