New Route to Synthesize Ultra‐Fine Zirconium Diboride Powders Using Inorganic–Organic Hybrid Precursors

Ultra‐fine zirconium diboride (ZrB 2 ) powders have been synthesized using inorganic–organic hybrid precursors of zirconium oxychloride (ZrOCl 2 ·8H 2 O), boric acid, and phenolic resin as sources of zirconia, boron oxide, and carbon, respectively. The reactions were substantially completed at a relatively low temperature (∼1500°C). The synthesized powders had a smaller average crystallite size (<200 nm), a larger specific surface area (∼32 m 2 /g), and a lower oxygen content (<1.0 wt%), which were superior to some commercially available ZrB 2 powders. The thermodynamic change in the ZrO 2 –B 2 O 3 –C system was mainly studied by thermogravimetric and differential thermal analysis. The crystallite size and morphology of the synthesized powders were characterized by transmission electron microscopy and scanning electron microscopy.