Synthesis, structure and highly selective C3H8/CH4 and C2H6/CH4 adsorption of a (4,8)-c ternary flu-metal–organic framework based upon both [Sc4O2(COO)8] and [Cu4OCl6] clusters

Abstract

A new ternary flu topological metal–organic framework based upon the torsional cubic 8-connected [Sc₄O₂(COO)₈] cluster and the tetrahedral 4-connected [Cu₄OCl₆] cluster, namely, [Sc₄O₂(Cu₄Cl₆O)₂(L)₈·5H₂O]·xGuest (SNNU-Bai69; SNNU-Bai = Shaanxi Normal University, Bai's group; HL = isonicotinic acid) has been successfully obtained by a solvothermal reaction of ScCl₃·6H₂O, Cu(NO₃)₂·3H₂O and HL. Very interestingly, this is the first ternary MOF based upon both the torsional cubic 8-connected [Sc₄O₂(COO)₈] cluster and the tetrahedral 4-connected [Cu₄OCl₆] cluster. Furthermore, its gas adsorption isotherms and breakthrough experiments reveal that it exhibits highly selective C₃H₈/CH₄, C₃H₈/C₂H₆ and C₂H₆/CH₄ adsorption and may be used for the pipeline natural gas upgrading.