Fig. 4: Regeneration energy of anion-functionalized MOFs and commercial zeolite 5A.

Comparison and relation between nHEX uptake at 16 kPa and regeneration temperature of ZU-72 with zeolite 5A (a). Time-dependent adsorbed amount profiles of nHEX on ZU-72 with zeolite 5A at 298 K (b). The nHEX adsorption–desorption cycles on ZU-72 and zeolite 5A at the regeneration temperature of 298 K (c). Calorimetric measurements of nHEX adsorption on ZU-72 and zeolite 5A (d). e, f The DFT-D calculated binding sites of nHEX within ZU-72 (e) and zeolite 5A (f). g, h Single-crystal structure of bare ZU-72 (g), ZU-72·nHEX (h). i, j The variation of the total energy as the pyridine ring and SnF₆²⁻ anions rotate around the lattice axis a/b and c, respectively, derived from DFT-D calculations. Schematic of the rotating units are shown as inset.