A (3,6)-connected metal–organic framework with high CH4 binding affinity and uptake capacity†
Abstract
A (3,6)-connected metal–organic framework with a fit-3 topology, [CuL(NO3)]·2DMF·H2O (NJU-Bai16), has been synthesized by self-assembly of binuclear [Cu2(COO)2N4] building blocks and heterofunctional ligand 3,5-di(pyridin-4-yl) benzoic acid (HL). The small pores within the framework have enabled their strong interactions with CH4 molecules. NJU-Bai16 was thereby found to exhibit high isosteric heats of CH4 adsorption (23.3 kJ mol−1) and uptake capacity (50.3 cm3 g−1 at 1 bar and 273 K). Additionally, NJU-Bai16 demonstrates high CO2 uptake (22.4 wt% at 1 bar) with excellent selectivity for CO2 over N2 (29.7) at 273 K.