NOVELTY - The method comprises storing a gas by applying a voltage to a device that comprises a support deposited on a gate of a power supply and a carbon-containing material deposited on the support. The support is present in electrical communication with the gate and with the carbon-containing material. The carbon-containing material is separated from the gate by the support. The power supply is configured to produce a voltage of -10 to +10 V across the device. The carbon-containing material is configured to adsorb gas responsive to the applied voltage, comprises single-walled carbon nanotubes.    USE - The method is useful for storing a gas such as hydrogen, oxygen, carbon dioxide, carbon monoxide, methane, ammonia or nitric oxide.    ADVANTAGE - The method is capable of storing the gas under an ambient or a higher pressure and ambient or higher temperature in an energy efficient and safe manner.    DETAILED DESCRIPTION - The method comprises storing a gas by applying a voltage to a device that comprises a support deposited on a gate of a power supply and a carbon-containing material deposited on the support. The support is present in electrical communication with the gate and with the carbon-containing material. The carbon-containing material is separated from the gate by the support. The power supply is configured to produce a voltage of -10 to +10 V across the device. The carbon-containing material is configured to adsorb gas responsive to the applied voltage, comprises single-walled carbon nanotubes, and has a length of 2 mu m. The method further comprises releasing the gas by decreasing the voltage of 5-50%. The carbon-containing material is doped with a metal. The support comprises a lower part, an upper part, a negative pole, and a positive pole. The negative pole of the power supply comprises the gate, and the positive pole of the power supply is connected to the upper part of the support.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of an apparatus for storing a gas.