本研究主要在探討稀磁性氧化物的磁性來源，透過化學沉澱法製備鈷摻雜的二氧化鈰奈米粒子，並藉由改變退火的氣氛、溫度和時間，來達到控制樣品中氧空缺的數量，並探討氧空缺與磁性間的關聯性。
我們以X光繞射儀觀察製備出的樣品為二氧化鈰的長程有序結構，確定晶相為面心立方的螢石結構，且沒有金屬鈷或鈷氧化物的相存在，並佐以高解析電子繞射顯微鏡觀察樣品的實際影像，確定奈米粒子的大小均勻，退火後的粒徑均維持在10nm左右，之後以X光精密吸收結構的分析，探測鈷原子的吸收邊以及短程有序結構，排除了形成了鈷金屬團簇的可能性，並確認鈷鑲嵌在二氧化鈰的主體中。接著利用電子能譜觀察退火後樣品中鈰原子的價數比例，確定不同的退火成功影響了樣品中的氧空缺濃度，並將氧空缺的濃度與超導量子干涉儀在室溫量測到的磁滯曲線整合比較，確定氧空缺的濃度與鐵磁性呈正相關性，符合BMP理論中磁性變化與氧空缺的濃度關係。

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