Hydrogen for novel materials and devices

We start by recalling some of the properties of hydrogen and present a summary of the phenomena caused by the reversible hydrogen sorption by metals and various forms of condensed carbon, at the surface and into the bulk, using molecular hydrogen gas, hydrogen plasma and electrochemically sorbed hydrogen. We then describe the use of hydrogen to modify the surface and bulk properties of various materials with a focus on applications and devices: electronic and optic phase transitions of thin films and related energy devices, surface polishing and cleaning, decrepitation and amorphization of intermetallics, growth of carbon nanostructures and electron emission from diamond-like and graphitic carbon, longrange perturbation of the electron distribution of graphitic structures by hydrogen defects, and the consequences for potential nanoelectronics. Received: 8 November 2000 / Accepted: 20 November 2000 / Published online: 9 February 2001