Hydrogen for novel materials and devices

We start by recalling some of the properties of hydrogen and present a summ ary of the phenomena caused by the reversible hydrogen sorption by metals a nd various forms of condensed carbon, at the surface and into the bulk. usi ng molecular hydrogen gas, hydrogen plasma and electrochemically sorbed hyd rogen. We then describe the use of hydrogen to modify the surface and bulk properties of various materials with a focus on applications and devices: e lectronic and optic phase transitions of thin films and related energy devi ces, surface polishing and cleaning, decrepitation and amorphization of int ermetallics, growth of carbon nanostructures and electron emission from dia mond-like and graphitic carbon, longrange perturbation of the electron dist ribution of graphitic structures by hydrogen defects, and the consequences for potential nanoelectronics.