An N-rich metal–organic framework with an rht topology: high CO2 and C2 hydrocarbons uptake and selective capture from CH4

We report the storage capacities and separation selectivity of an rht-type s-heptazine-based metal organic framework (MOF), Cu3(TDPAH)(H2O)3·13H2O·8DMA, 1, (where TDPAH is 2,5,8-tris(3,5-dicarboxylphenylamino)-s-heptazine and DMA is N,N-dimethylacetamide) for C2 hydrocarbons and CO2 over CH4. MOF 1 displays the highest C2H2/CH4 selectivity of 80.9 as well as record high C2H4 and C2H6 adsorption enthalpies. Theoretical calculations reveal that s-heptazine and NH groups within the framework have synergistic effects on CO2 binding.