Electrostatic Potential Matching in an Anion‐Pillared Framework for Benchmark Hexafluoroethane Purification from Ternary Mixture

Abstract One‐step purification of CF 3 CF 3 from ternary CF 3 CH 2 F/CF 3 CHF 2 /CF 3 CF 3 mixture is crucial since its vital role in the semiconductor industry. However, efficient separation of chemically inert CF₃CF₃ remains challenging due to the difficulty in creating specific recognition sites in porous materials. In this work, we report the first example of anion‐pillared MOFs to the separation of fluorinated electronic specialty gases, utilizing the unique electrostatic potential matching in the bipolar pores of SIFSIX‐1‐Cu to realize a benchmark CF 3 CH 2 F/CF 3 CHF 2 /CF 3 CF 3 separation. SIFSIX‐1‐Cu exhibits the highest CF 3 CH 2 F and CF 3 CHF 2 adsorption capacity at 0.01 bar, as well as the highest CF 3 CH 2 F/CF 3 CF 3 and CF 3 CHF 2 /CF 3 CF 3 IAST selectivity. Additionally, high‐purity (≥ 99.995%) CF 3 CF 3 with record productivity (882.9 L kg −1 ) can be acquired through one‐step breakthrough experiment of CF 3 CH 2 F/CF 3 CHF 2 /CF 3 CF 3 (5/5/90). Theoretical calculations further reveal that the coexistence of electronegative SiF 6 2− and partially electropositive H sites promotes SIFSIX‐1‐Cu to effectively anchor CF 3 CH 2 F and CF 3 CHF 2 through multiple supramolecular interactions.