本研究首先利用水熱法合成出氫氧碳酸鈰(Ce(OH)CO3)奈米片，在空氣下煆燒後可得到二氧化鈰(CeO2)奈米片，其尺寸可達數微米，厚度可約為200奈米。此種奈米片結晶良好，但表面粗糙，且有很多小顆粒附著。為了改善奈米片表面粗糙度及缺陷結構，將所製備的奈米片以兩種不同方式進行表面改質。第一種是在進行煆燒前，先將氫氧碳酸鈰奈米片與硝酸溶液反應2至10分鐘。
實驗結果顯示經過硝酸溶液處理的樣品，可成功去除表面附著的小顆粒，而奈米片中的缺陷(Ce3+)濃度隨著硝酸處理時間增加呈現先上升再下降的趨勢。所有樣品均呈現室溫鐵磁性，在經過硝酸處理5分鐘的樣品具有最高的飽和磁化量。
第二種改質方式是將在空氣下煆燒後的二氧化鈰奈米片，在還原氣氛下進行退火。結果顯示樣品的尺寸形貌及表面無顯著變化。樣品的缺陷含量隨著還原溫度上升而明顯增加，但使用更高的還原溫度下，缺陷含量卻有所下降。觀察到樣品所含的缺陷含量與飽和磁化量也有著相似的趨勢。在綜合比較下可以發現，經過還原的三個樣品整體缺陷含量都較高，而擁有最強磁性之樣品為經過300 ℃還原的奈米片，並且發現樣品磁性量測結果會隨著缺量含量變化而有所改變。

This study first synthesized cerium hydroxide carbonate (Ce(OH)CO3) triangular nanosheets by hydrothermal method. Then Cerium oxide (CeO2) nanosheets can be obtained after sintering under air. Its size can reach several microns, and its thickness is about 200 nm. The nanosheet is well crystallized, but the surface is rough, and many small particles are attached. In order to adjust the structure of the nanosheets, two different post-treatments were performed. The first is the reaction with the nitric acid solution for 2 to 10 minutes before calcination. It shows that the reaction with nitric acid can successfully remove small particles attached to the surface. The concentration of defects (Ce3+) in the nanosheets increased with the reaction time. All samples exhibit room-temperature ferromagnetism.
The second modification method is annealing in a reducing atmosphere. No significant change in the samples’ size, morphology, and surface were observed. However, the defect content of the sample increases obviously with the increase of the reduction temperature. It is observed that the defect content contained in the samples has a similar trend with saturation magnetization. The highest saturation magnetization was obtained in the nanosheet that has been reduced at 300 °C.

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