Hydrogen in nanostructures

The present experimental knowledge of the properties of hydrogen nanostructures is reviewed. The behavior of hydrogen is discussed for nanomaterials made from metals, alloys, intermetallics, and semiconductors (silicon, germanium, etc.), as well as from fullerenes and carbon and other nanotubes. Methods for fabricating nanostructures from these objects are briefly outlined. Structural features, defects, solubility and diffusion mobilities, and thermodynamic and physical properties are discussed. Some aspects still to be clarified are pointed out.