利用固態反應法，添加不同量的 Ni2+ 取代鍺酸鑭基磷灰石材料 (La9.5Ge6-xNixO26.25-x，x = 0，0.1，0.15，0.2，0.25，0.5，0.75，1)，觀察晶體結構的變化及與導電性質間的關聯性。
實驗結果顯示當鎳的添加量約在 x = 0.25 以上時，從 XRD 圖譜上觀察到二次相 LaNiO3 的生成，推測已超出其固溶範圍。將合成後的粉末以 Rietveld 方法模擬精算結構因子後，發現未添加鎳之樣品，其結構為六方晶系 (P63/m)，且假設晶體結構中最大處，為間隙氧最可能通過之區域，模擬出 4 條間隙氧可能移動之類正弦路徑。而添加鎳之樣品，其結構為三斜晶系 (Pī)，且結構中存在一瓶頸處，使得間隙氧通過困難，導致導電率降低。並經由相關文獻比對之後，發現其活化能較未添加鎳之樣品高，其原因應為結構發生相變化而導致。
經由拉曼光譜分析和文獻比對，發現鍺酸鑭基系統其導電機制為間隙氧離子，而隨鎳添加量增加，用以導電之載體間隙氧離子數目減少，導致導電率降低。

Apatite materials based on lanthanum germanates and doped with nickel (La9.5Ge6−xNixO26.25−x, x = 0, 0.1, 0.15, 0.2, 0.25, 0.5, 0.75, 1) were prepared to synthesize a single phase through solid-state method. XRD patterns indicate that the second phase (LaNiO3) existed when x = 0.25. Accordingly, the limit of solid solubility (x) was approximately 0.25. A single phase could be obtained when the compositional range was 0 ≤ x ≤ 0.25. Crystal structure analysis refined through the Rietveld method distinctly showed that the sample when x = 0 has a hexagonal structure (P63/m). From this result, four possible migration pathways may be established if the interstitial oxygen passes through the largest region in the entire crystal structure. These four pathways are screwlike, three-dimensional routes around the c axis for nickel-doped samples, which have triclinic structure. Because of the complicated structure, migration of interstitial oxygen becomes very difficult. The relationship between the decrease in conductivity and the decrease in interstitial oxygens may be explained by Raman spectroscopy.

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