NOVELTY - A composite comprises carbon-based foam and solid state hydrogen storage material.    USE - For storing hydrogen used in system incorporated with a fuel cell to provide energy.    ADVANTAGE - The composite is capable of releasing hydrogen at a lower temperature to provide increased amount of hydrogen released from the composite or to increase or control the rate at which hydrogen is released from the composite.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for:    (1) a method for making a carbon cryogel comprising preparing a sol by mixing a catalyst and greater than or equal to2 components capable of forming an organic sol-gel in water; gelling the sol by heating at a temperature and for a time to provide a gel; drying the gel to provide a polymer foam; pyrolyzing the polymer foam to provide a carbon-based foam; and contacting the carbon-based foam with a solid state hydrogen storage material that infiltrates the carbon-based foam to provide a carbon-based foam composite;    (2) a method for hydrogen storage comprising contacting a vessel containing the hydrogen storage material with hydrogen;    (3) a gas storage vessel;    (4) a method for charging the carbon-based foam composite with the solid state hydrogen storage material;    (5) a system comprising the hydrogen storage vessel and a fuel cell capable of converting hydrogen into energy; and    (6) a method for lowering the temperature required for releasing hydrogen from the solid state hydrogen storage material, comprising contacting a carbon-based foam with a solid state hydrogen storage material having a first hydrogen release temperature, to provide a composite having a second hydrogen release temperature lower than the first hydrogen release temperature.    DESCRIPTION OF DRAWING(S) - The figure is a graph showing comparison of hydrogen release from ammonia borane (AB) and a carbon cryogel loaded with AB, with which the carbon cryogel loaded with AB releases hydrogen at a temperature lower than AB.