Reversible Methane Storage in a Polymer-Supported Semi-Clathrate Hydrate at Ambient Temperature and Pressure

A key issue regarding the use of clathrates and semi-clathrate hydrates for practical gas storage is the pressure−temperature stability of the material. For many practical applications, the avoidance of cooling, gas overpressure, and mechanical mixing would be very desirable. Here, we show that porous emulsion-templated polymer supports greatly enhance methane uptake kinetics in tetra- iso -amylammonium bromide semi-clathrate hydrates without introducing complex mixing technologies. These systems show unprecedented thermal stability and can be decomposed upon demand to release the gas. Single crystal X-ray structure analysis of the semi-clathrates loaded with methane or krypton were obtained, confirming that the gases are stored in the dodecahedral A′ and A′′ cages.