An Aluminum-Based Metal–Organic Framework Incorporating Al₃ and Al₉ Nodes with High Porosity

Aluminum-based metal–organic frameworks (Al-MOFs) are characterized by structural diversity, high stability, low density, and nontoxicity, making them well-suited for adsorption related applications, yet their synthesis and characterization remain challenging. In this work, we report an Al-MOF, namely, HIAM-340, constructed from a hexacarboxylate linker, which incorporates unique Al3 and Al9 clusters and features a novel 5,4,9-c topology. It demonstrates a robust framework and high porosity with a BET surface area of 2800 m2 g–1. HIAM-340 exhibits an S-shaped water adsorption isotherm, with a saturation uptake of 52.02 mmol g–1 at 298 K and 1 bar. Additionally, we showcase that HIAM-340 is capable of separating ethane/ethylene/acetylene ternary mixtures in a single step through selective adsorption. This study offers valuable insights into crafting Al-MOFs via linker design, aiming for their potential use in adsorption-related applications.