Overcoming the Trade‐Off between C <sub>2</sub> H <sub>2</sub> Sorption and Separation Performance by Regulating Metal‐Alkyne Chemical Interaction in Metal‐Organic Frameworks
Yan‐Xi Tan, Jing Lin, Qiaohong Li, Liqiong Li, Rahul Anil Borse, Weigang Lu, Yaobing Wang, Daqiang Yuan
Abstract
Abstract Designing porous materials for C 2 H 2 purification and safe storage is essential research for industrial utilization. We emphatically regulate the metal‐alkyne interaction of Pd II and Pt II on C 2 H 2 sorption and C 2 H 2 /CO 2 separation in two isostructural NbO metal–organic frameworks (MOFs), Pd/Cu‐PDA and Pt/Cu‐PDA . The experimental investigations and systematic theoretical calculations reveal that Pd II in Pd/Cu‐PDA undergoes spontaneous chemical reaction with C 2 H 2 , leading to irreversible structural collapse and loss of C 2 H 2 /CO 2 sorption and separation. Contrarily, Pt II in Pt/Cu‐PDA shows strong di‐σ bond interaction with C 2 H 2 to form specific π‐complexation, contributing to high C 2 H 2 capture (28.7 cm 3 g −1 at 0.01 bar and 153 cm 3 g −1 at 1 bar). The reusable Pt/Cu‐PDA efficiently separates C 2 H 2 from C 2 H 2 /CO 2 mixtures with satisfying selectivity and C 2 H 2 capacity (37 min g −1 ). This research provides valuable insight into designing high‐performance MOFs for gas sorption and separation.