Synthesis of the tetragonal titanium dihydride in ultradispersed state

The ultradispersed tetragonal titanium dihydride (specific surface of 10-55 m(2)/g, the average size of particles of 15-40 nm), stabilized by 0.1-0.15 atom of nitrogen per molecule of the titanium dihydride, was prepared by a n interaction of the titanium powder with ammonia under a pressure of 0.7-0 .8 MPa in a presence of the ammonium chloride. The influence of a size of t he particles of the initial titanium powder (10-100 mcm) and a temperature (200-400 degrees C) on a direction of an interaction and on a state (microc rystalline or ultradispersed) of the titanium dihydride was investigated. I t has been established that the derived titanium dihydride crystallizes int o a tetragonal lattice with the constants a(o) = 4.468 Angstrom, c(o) = 4.3 91 Angstrom and is resistant in an inert atmosphere to 600 degrees C. (C) 1 999 International Association for Hydrogen Energy. Published by Elsevier Sc ience Ltd. All rights reserved.