Recent advances in the design of metal–organic frameworks for methane storage and delivery

Metal–organic framework (MOF) adsorbents can store and deliver methane for vehicular energy. To improve methane storage and deliverable capacity, these porous crystalline materials can be designed. In this review, recent advances in design strategies of MOFs are highlighted that were achieved through reticular synthesis. For the first time, the 2012 Department of Energy (Department of Energy = DOE) target of a gravimetric capacity of 0.5 g (methane) g⁻¹ was experimentally met. A discussion of how this was achieved is provided through the careful alteration of the pore metrics, linker, functionality, and adsorption sites of the porous material. In addition, the synthesis of new MOF structures was reported which have mesoporosity and breathing properties. Recently, adsorption testing was performed at higher pressures (200 bar) and lower temperatures than ever before for MOFs. For some MOFs, gravimetric and volumetric uptakes increase at lower temperatures than 298 K and pressures higher than 65 bar.