Effective hydrogen isotope separation by a robust flexible calix[4]resorcinarene-based porous organic cage

Abstract

Herein, we present the design and synthesis of a new [6 + 12] octahedral-type porous organic cage (POC), namely CPOC-F301, assembled from 6 bowl-shaped tetraformylcalix[4]resorcinarene and 12 flexible trans-1,4-cyclohexanediamine. This cage exhibits large cavity volumes of up to ∼3824 ų, high specific surface areas of up to 966 m² g⁻¹, and impressive D₂ (146 cm³ g⁻¹) and H₂ (133 cm³ g⁻¹) adsorption capabilities at 77 K and 1 bar. Dynamic breakthrough experiments further demonstrate that CPOC-F301 achieves a separation factor of 1.37 with a breakthrough interval of 7.2 min g⁻¹ at 77 K and 1 bar.