Abstract
A nanocapsule is investigated for methane storage purposes. The nanocapsule is a 'bucky shuttle' (or a nanopeapod) with a hole in its structure. The bucky shuttle has a diameter of a nanotube (10, 10) and is 180 A in length. A K@C-60(1+) endohedral complex is encapsulated into the nanocapsule. Simulations are performed by a molecular dynamics method. The internal dynamics of the system are investigated - the nanocapsule, the K@C-60(1+) endohedral complex and methane molecules. The closing of the nanocapsule can be induced by the K@C-60(1+) ion transition as a result of applying an electric field. There is no need to keep the electric field at the storage stage, because the K@C-60(1+) ion cannot overcome the hole area owing to the effect of forces created in the hole of the nanocapsule. The opening of the nanocapsule takes place under the heating of the system. It is shown that this is a temperature-sensitive nanocapsule for methane molecule storage under zero external pressure and a temperature of 300 K. The nanocapsule retains 71 methane molecules (3.06 mass%) and releases gas at 350 K.