De‐Linker‐Enabled Exceptional Volumetric Acetylene Storage Capacity and Benchmark C2H2/C2H4and C2H2/CO2Separations in Metal–Organic Frameworks

Abstract

AbstractAn ideal adsorbent for separation requires optimizing both storage capacity and selectivity, but maximizing both or achieving a desired balance remain challenging. Herein, a de‐linker strategy is proposed to address this issue for metal–organic frameworks (MOFs). Broadly speaking, the de‐linker idea targets a class of materials that may be viewed as being intermediate between zeolites and MOFs. Its feasibility is shown here by a series of ultra‐microporous MOFs (SNNU‐98‐M, M=Mn, Co, Ni, Zn). SNNU‐98 exhibit high volumetric C2H2uptake capacity under low and ambient pressures (175.3 cm3 cm−3@ 0.1 bar, 222.9 cm3 cm−3@ 1 bar, 298 K), as well as extraordinary selectivity (2405.7 for C2H2/C2H4, 22.7 for C2H2/CO2). Remarkably, SNNU‐98‐Mn can efficiently separate C2H2from C2H2/CO2and C2H2/C2H4mixtures with a benchmark C2H2/C2H4(1/99) breakthrough time of 2325 min g−1, and produce 99.9999 % C2H4with a productivity up to 64.6 mmol g−1, surpassing values of reported MOF adsorbents.