SUBSTANCE OCCLUDING MATERIAL AND ELECTROCHEMICAL DEVICE USING IT, AND PRODUCTION METHOD FOR SUBSTANCE OCCLUDING MATERIAL

Disclosed are a substance-occluding material being high in efficiency, being lightweight, inexpensive and safe, and being high in transportability, an electrochemical device using the same, and a method of producing the substance-occluding material. A substance-occluding material wherein a substance, for example, a fullerene molecule (C), different from a substance to be occluded such as hydrogen gas is contained in the inside of a tubular material such as a carbon nanotube. A substance-occluding material wherein tubular materials such as carbon nanotubes or rod-like materials such as carbon nanofibers are densely bundled to form a bundle structure, and a substance to be occluded such as hydrogen gas is occluded between the tubular or rod-like materials. A substance-occluding material wherein a tubular material has a multi-wall structure, and a space portion for occluding a substance to be occluded is formed on the innermost side of the structure. A method of producing the substance-occluding material, including a step of treating the substance-occluding material with a base. An electrochemical device wherein a hydrogen-occluding material as the substance-occluding material according to the present invention is used.