NOVELTY - A combined hydrogen production and reversible hydrogen storage process involves adding energy to mixture of carbon and hydrogen source under moderate temperature and pressure reaction conditions such that hydrogen is generated and/or released from hydrogen source, to form an amorphous diamond-like carbon, and at least a portion of the hydrogen generated and/or released is associated with amorphous diamond-like carbon, forming hydrogenated carbon material including hydrogen carbon clathrate, to produce hydrogen and storing hydrogen as stored hydrogen.    USE - For generating hydrogen, storing hydrogen in carbon-based storage material and/or evolving hydrogen from the storage material (claimed) for use in powering vehicle or portable device.    ADVANTAGE - The combined hydrogen production-storage process improves overall system efficiency. Modification of low-cost anthracite coals into hydrogenated carbon materials, that evolve hydrogen provide a viable alternative to solid-state hydrogen storage materials that rely on reversible thermodynamics, for which DOE storage targets are difficult. The combined storage and production process traps molecular hydrogen within a sequestered carbon matrix; reduces energy and material costs of hydrogen production and storage associated with a separate storage step having associated material production and adsorption energy penalties. The process of combined synthesis of hydrogen storage material, hydrogen generation and/or release from a hydrogen source and storage of the hydrogen in the hydrogen storage material, obviating the need for separate generation of a hydrogen storage medium, separate generation of hydrogen, and transport of hydrogen to the hydrogen storage medium for storage. The composition and process is able to both generate hydrogen and store the generated hydrogen; and allows for significant cost and time savings by eliminating the need and equipment used for transport of generated hydrogen to a separate storage material, pressurization and heat transfer of separately generated hydrogen.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) producing hydrogen from a hydrogen source involves contacting an amorphous diamond-like carbon dehydrogenation catalyst and a hydrogen source under dehydrogenation reaction conditions, to generating and/or releasing hydrogen from the hydrogen source and producing hydrogen;    (2) a composition comprising a hydrogenated carbon material including a hydrogen-carbon clathrate, the hydrogenated carbon material containing a hydrogen carbon clathrate characterized by evolution of molecular hydrogen at room temperature at atmospheric pressure; and    (3) a composition comprising a dehydrogenation material to dehydrogenate a hydrogen-containing material, the dehydrogenation material containing a carbon-based product of high energy milling of a carbon source.