Ethanol‐Water‐Derived Sucrose‐Coated‐Al 2 O 3 for Submicrometer AlON Powder Synthesis

Fluffy and homogenous sucrose‐coated‐γ‐Al 2 O 3 structured precursor was prepared by drying ethanol‐water sucrose/Al 2 O 3 suspension, in which the ethanol content of 85 vol% was optimized. Using the C/Al 2 O 3 mixture pyrolyzed from such precursor with 23.2 wt% sucrose, single‐phase AlON powder was synthesized by two‐step carbothermal reduction and nitridation method at 1550°C for 2 h and 1700°C for another 1.5 h. The particle size of the AlON powder was around 0.6–1.0 μm. Compared with those synthesized by the traditional approaches with mechanical C/Al 2 O 3 , Al/Al 2 O 3 , or AlN/Al 2 O 3 mixtures, the synthesis temperature was reduced about 50°C, and the AlON powder was fine and exhibited good dispersity. Such superiority of this method was attributed to that the pyrolyzed carbon film on Al 2 O 3 particle greatly restrained Al 2 O 3 coalescence during the thermal treatment.