【摘要】 以分析纯Bi（NO₃）₃·5H₂O和Y（NO₃）·6H₂O为原料制备纳米β-Bi₂O₃和Bi₂O₃-Y₂O₃（75% （摩尔分数）Bi₂O₃+25%（摩尔分数）Y₂O₃）粉体,平均粒度分别为40和30nm。经TG-DTA、高温XRD以及高温拉曼的研究结果表明。亚稳态的纳米β-Bi₂O₃粉体在升温过程中于420℃先向低温稳定的α-Bi₂O₃转变,在720℃时向δ-Bi₂O₃相转变,降温过程则是由δ→p→α。由于纳米Bi₂O₃具有很高的活性,使得相变温度比微米Bi₂O₃有所降低。蚋米Bi₂O₃-Y₂O₃复合粉体升温过程中。Y₂O₃的固溶反应在较低温度（400℃）开始,500℃时β-Bi₂O₃完全转变为δ相,同时Y₂O₃完全固溶到δ-Bi₂O₃晶体中。Y₂O₃的掺杂使得Bi₂O₃的β→δ相转变温度大幅降低。更多还原

【Abstract】 With A.R.Bi（NO₃）₃·5H₂O and Y（NO₃）₃·6H₂O as raw materials,nano Bi₂O₃ and Bi₂O₃-Y₂O₃ （75mol%Bi₂O₃+25mol%Y₂O₃） powders were prepared and the average grain sizes were less than 40 and 30nm, respectively.The study results of TG-DTA,high temperature XRD and high temperature Raman on phase tran- sition behave of these powders showed that metastable state nanometerβ-Bi₂O₃ transformed into stableα-Bi₂O₃ at low temperature （420℃） first,thenα-Bi₂O₃ transitioned intoδ-Bi₂O₃ at 720℃during the heated process; during the cooled process,phase transformation process wasδ→β→α,because nano-Bi₂O₃ has higher activity which lead to lower transition temperature than micron-Bi₂O₃.The solid solution reaction of Y₂O₃ andβ-Bi₂O₃ started at lower temperature （400℃） during the process of heated mixed nano Bi₂O₃-Y₂O₃ powder,b-Bi₂O₃ had almost completely transformed intoδ-Bi₂O₃ at 500℃and the solid solution reaction turned to end.Theβ→δphase transformation temperature was lowered obviously by doping of Y₂O₃.更多还原