Substitution of H- for O- and H- emissions of 12CaO•7Al2O3 -: art. no. 114101

By using an anion-exchanging method, about 90% of the O- anions in the C12A7-O- microporous crystal ([Ca24Al28O64](4+)center dot 4O(-)) have been substituted primarily by the H- anions, leading to the successful formation of a new H- emission material, C12A7-H- ([Ca24Al28O64](4+)center dot 4H(-)). A sustainable and stable emission of H-, in a current density of mu A/cm(2) level, has been obtained by supplying H-2 and electrons on the backside of the C12A7-H- sample. The emission features of C12A7-H-, including temperature and field effects, have been investigated. It is expected that the present material could be practically used as an H- anion generator. (C) 2005 American Institute of Physics.