Preparation of alumina/AlON and AlON/AlN composites from Al2O3/Carbon nanocomposite by solvothermal method

Abstract

Al2O3/Aluminum oxynitride (AlON) and AlON/ Aluminum nitride (AlN) composites were prepared via two-step carbothermal reduction nitridation (CRN) method. A solvothermal method was selected to synthesize alumina (Al2O3)/Polyacrylonitrile (PAN) nanocomposite as a first-precursor of products. Then, this Al2O3/PAN sample was held under pyrolysis conditions (800 °C for 2 h in an argon atmosphere) for fabricating Al2O3/Carbon nanocomposite. Eventually, using two-step CRN method (first at 1450–1550 °C for 2 h in argon (Ar) flow and so 1700–1800 °C for 1 h in N2 flow) Al2O3/AlON and AlON/AlN composites were achieved. Results show that a change in the residual carbon content in second-precursor (alumina/carbon nanocomposite) is a key factor in controlling the composition of the final product.