近日，三峡大学李东升团队揭示了等晶格金属-有机框架的空间交互协同约束促进C₂H₂与CO₂的分离。这一研究成果发表在2025年7月1日出版的《美国化学会志》上。

在多孔材料中同步实现精确的分子识别和有效的气体积累是非常理想的，但对于物理分离/存储应用具有挑战性。

研究组证明了通过调节三种同构柱状层状MOF（CTGU-41/42/43）的孔径和互穿对称性，从具有创纪录高气体堆积密度的C₂H₂/CO₂混合物中有效纯化乙炔（C₂H₂）的可行性。一维矩形窄通道和规则排列的配对结合位点触发空间相互作用协同约束（SISC），在这些MOF内吸附C₂H₂时实现合适的分子取向和间距距离。

特别是CTGU-41对C₂H₂/CO₂混合物（v/v, 50/50）表现出优异的吸附选择性（41.4），在298 K和100 kPa下，C₂H₂的储存密度达到了创纪录的0.91 g mL^-1，据他们所知，首次超过了固体C₂H₂（4.2 K）的密度。通过柱突实验进一步验证CTGU-41/42/43的实际C₂H₂/CO₂分离能力，C₂H₂纯度高（>99.0%），分离系数高（6.7 ~ 11.3）。该工作阐明的SISC机理加深了对特定吸附空间致密气体排列的基本认识，可推广到其他具有挑战性的气体分离和储存应用中。

附：英文原文

Title: Spatial-Interactive Synergistic Confinement in Isoreticular Metal–Organic Frameworks for Facilitating C2H2 Separation from CO2 with Record Packing Density

Author: Xue-Qian Wu, Cai-Lian Liao, Jun-Jie Wu, Peng-Dan Zhang, Guangtong Hai, Meidi Wang, Ya-Pan Wu, Jian-Rong Li, Dong-Sheng Li

Issue&Volume: July 1, 2025

Abstract: The synchronous implementation of precise molecule recognition and efficient gas accumulation in porous materials is highly desirable but challenging for physisorptive separation/storage applications. Here, we demonstrate the feasibility of achieving effective acetylene (C2H2) purification from a C2H2/CO2 mixture with record-high gas packing density by modulating the pore size and interpenetrating symmetry in three isomorphic pillar-layered MOFs (CTGU-41/42/43). The 1D rectangular narrow channels and regularly arranged paired binding sites trigger spatial-interactive synergistic confinement (SISC), enabling suitable molecular orientation and spacing distances during C2H2 adsorption within these MOFs. In particular,  CTGU-41 exhibits exceptional adsorption selectivity (41.4) toward the C2H2/CO2 mixture (v/v, 50/50) with a record-high C2H2 storage density of 0.91 g mL–1 at 298 K and 100 kPa, which, to the best of our knowledge, surpasses the density of solid-C2H2 (4.2 K) for the first time. The practical C2H2/CO2 separation ability of CTGU-41/42/43 is further validated by column breakthrough experiments with high purity of C2H2 (>99.0%) and good separation factors (6.7–11.3). The SISC mechanism clarified in this work deepens the fundamental understanding of dense gas arrangement in specific adsorption space, which can be generalized to other challenging gas separation and storage applications.

DOI: 10.1021/jacs.5c05650

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c05650