SOLID-STATE METATHESIS ROUTES TO METAL NITRIDES - USE OF STRONTIUM AND BARIUM NITRIDES AS REAGENTS AND DILUTION EFFECTS

Bulk thermal or filament initiated reactions of mixed powders of trans ition metal chlorides and Sr2N and Ba3N2 produce transition metal nitr ides (TiN, ZrN, HfN, VN, V2N) in good yield. The products were charact erised by X-ray powder diffraction, SEM/EDAX, FT-IR, microelemental an alysis and imaging XPS. The affect of diluting the reaction by the add ition of LiCl was used to lower reaction temperatures and in the case of WCl4, and Li3N produced WN. Reaction propagation was investigated b y using various mixtures of nitriding reagent (Li3N, Mg3N2, Ca3N2), th is was correlated with T-ad,T-s, the maximum adiabatic combustion temp erature for salt formation only. (C) 1997 Elsevier Science Ltd.