溶胶—凝胶法制备Al_2O_3纳米粉

SYNTHESIS OF NANOCRYSTALLINE ALUMINA POWDER WITH SOL-GEL METHOD

以Al(NO3) 3和NH3·H2 O为原料制备AlOOH勃姆石溶胶 ,加入PVA作为分散剂 ,干燥后制成干凝胶。干凝胶经不同温度下煅烧得到不同晶型的Al2 O3纳米粉。X—射线衍射分析结果表明 ,勃姆石干凝胶在煅烧过程中的物相变化为AlOOH→ε-Al2 O3→ -Al2 O3→δ -Al2 O3→θ -Al2 O3→α-Al2 O3,采用电子显微镜和BET比表面积法测量出Al2

AlOOH boehmite sol was prepared by sol gel method with Al(NO\-3)\-3 and NH\-3·H\-2O as raw materials.Some PVA were added into the sol,then dry to form dry AlOOH gel .The different kinds of Al\-2O\-3 nanocrstallines were obtained by calcining the dry gel at different calcining temperature.XRD results indicate that the phase transformation sequence of dry AlOOH gel during heating is AlOOH→ε-Al\-2O\-3→-Al\-2O\-3→δ-Al\-2O\-3→θ-Al\-2O\-3→α-Al\-2O\-3.The powder size of Al\-2O\-3 nanocrystallines were detected with electronic microscope and BET method.