Porous MOFs with geometric mismatch between trimers and octatopic pyrene-based ligands for low-temperature methane storage

Abstract

Natural gas is recognized as a transitional clean energy fuel to address a variety of environmental problems. Identifying porous adsorbents with high-capacity low-temperature methane adsorption performances is crucial for advancing next-generation technologies for efficiently utilizing boil-off gas, inevitablely generated from liquefied natural gas systems. Herein, we synthesized highly porous metal–organic frameworks (MOFs)-TBPP-MOFs with a geometric mismatch strategy by combining seemingly incompatible trinuclear clusters with octatopic pyrene-based ligands. The Cr-TBPP-MOF achieves a high apparent Brunauer–Emmett–Teller (BET) surface area of 3700 m² g⁻¹ and demonstrates pore volumes of 1.31 cm³ g⁻¹ at P/P₀ = 0.9. Consequently, under the LNG–ANG coupling operation conditions, Cr-TBPP-MOF exhibits a high low-temperature methane uptake of 335 cm³ (STP) cm⁻³ at 159 K and 10 bar with a working capacity of 302 cm³ (STP) cm⁻³ between 6 bar and 159 K to 5 bar and 298 K, positioning it as a promising candidate material for low-temperature methane adsorption.