A pure-supramolecular-linker (PSL) approach for the formation of metal-organic frameworks (MOFs) was initially given, which was demonstrated by syntheses of two highly connected and isostructural MOFs, {Fe3O(TPBTM6-)(Cl)(H2O)(2)}(infinity) (TPBTM = N,N',N ''-tris(isophthalyl)-1,3,5-benzenetricarboxamide) (NJU-Bai52, NJU-Bai for Nanjing University Bai group) and {Sc3O(TPBTM6-)(OH)(H2O)(2)}(infinity) (NJU-Bai53). Very interestingly, they exhibit exceptional thermal stability, water stability, and highly selective CO2 capture properties. In particular, NJU-Bai53 with higher uptakes (2.74 wt % at 0.4 mbar and 298 K, 7.67 wt % at 298 K and 0.15 bar) and higher selectivity may be an excellent candidate for CO2 capture.