摘要
以Fe（NO3）3·9H2O2为源物质，乙二醇为溶剂，用Sol－gel法制备了平均粒径为10nm的γ-Fe2O3和掺Y2O3的γ-Fe2O3超细粉，并同时对样品的热稳定性、物相、微结构和气敏性能作了分析和测定．结果表明，掺入适量Y2O3后能使γ-Fe2O3的相变温度提高到775℃，这将使γ-Fe2O3基气敏元件的稳定性得到改善．两种超细粉制成的旁热式厚膜气敏元件对H2和CO几乎不敏感，而对C2H5OH、C2H2、液化石油气（LPG）和汽油则有较高的灵敏度．
Ultra-fine powders of γ-Fe2O3 and 12. 4mol%Y2O3 doped γ-Fe2O3 with average particle size 0f 10nm have been prepared by a polymeric Sol-gel process. The study of material thermal stability, phases, micro-structure and gas-sensing properties of γ-Fe2O3 doped with Y2O3 shows that the phase transition temperature is 775℃, which is much higher than that of the undoped sample(390℃ ). This indicates that the existence of Y2O3 improves the stability of gas-sensing material. The sensors made of γ-Fe2O3 and 12.4mol%Y2O3 doped γ-Fe2O3 powders exhibit high sensitivity to C2H5OH, C2H2, LPG and petrol, but are almost insensitive to H2 and CO.
基金
国家自然科学基金
