No abstract

High pure ZrN nanopowder was synthesized from Z-U or ZO-U precusors by using ZrCl 4 and ZrOCl 2 •8H 2 O as zirconium source, urea as solid N source. The preceramic precursors characterized by FT-IR were prepared via coordination between zirconium ions and urea molecules. Both precursors were further pyrolyzed at relatively low temperatures to yield ZrN. XRD and SEM techniques were used to examine the microstructures of the ceramic powders, while TG-DTA was used to study the pyrolysis process. It appears that the crystal water has strong effect on the coordination chemistry of Zr ions, resulting in obvious differences in molecular structures of two precursors. Such structural differences have strong effects on purity and morphologies of the as-prepared ZrN nanopowder. Apparently, the Z-U precursor from ZrCl 4 is more liable to acquire high pure ZrN nanopowder.