Tailoring the Pore Environment of a Robust Ga-MOF by Deformed [Ga₃O(COO)₆] Cluster for Boosting C₂H₂ Uptake and Separation

The construction of superstable metal–organic frameworks (MOFs) for selective gas uptake is urgently demanded but remains a great challenge. Herein, a unique bifunctional deformed [Ga₃O­(COO)₆] inorganic secondary building unit (SBU) generated from the desymmetrical evolution of typical triangular prismatic trinuclear cluster was first introduced, which was extended by an isosceles triangular organic linker to produce a robust Ga-MOF (SNNU-63). Remarkably, SNNU-63 can stabilize in water at 25 °C for 96 h and at 80 °C for more than 24 h, which surpasses nearly all other Ga-MOFs. The combined effects of open metal sites and hydrophobic pore environment provided by deformed [Ga₃O] SBUs render SNNU-63 with high C₂H₂ storage capacity and efficient C₂H₂ and natural gas purification performance. The ideal adsorbed solution theory calculation, column breakthrough tests, and grand canonical Monte Carlo simulations demonstrate that SNNU-63 is a potential material for addressing the challenge of C₂H₂/CO₂ and C₂H₂/CH₄ mixture separation under ambient conditions.