本研究利用固相反應法合成鎢摻雜鍺酸鑭基磷灰石電解質材料，藉由添加不同量的 W6+ 取代La9.5Ge6-xWxO26.25+x 中的Ge4+ 位置 (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。
實驗結果顯示當鎢的添加量達到 x = 0.25 時，有明顯二次相生成，推測已超出固溶範圍。將煅燒後的粉末以 Rietveld 方法模擬精算晶格常數後，可觀察到鎢添加會使鍺氧四面體產生改變，且四面體上 O3周遭晶體結構變化較明顯，由此區域假設為間隙式氧離子移動所經過的空間，可模擬類似於文獻上間隙式氧離子移動的路徑。
不同成分點之試片燒結緻密條件不同，以 1450℃ 燒結後相對密度達 95% 以上之試片，在 800℃，x = 0.15、0.2 時具有較高導電率 (0.0366、0.0398 S/cm)，且 x = 0.2 在晶體結構中具有最大的 O4-O3 距離 3.3376Å 與最大的O3-La2距離 3.4838Å (長邊)，推測此添加量在固溶極限內將晶格扭曲，擴大間隙式氧離子移動通道，使間隙式氧離子易於移動而具有較高導電性；當 x = 0.25 時含有較多二次相則會使導電率下降。

Lanthanum oxygermanate apatite electrolyte, doped with tungsten (W), La9.5Ge6-xWxO26.25+x , was synthesized using a solid-state reaction method. Single phases were obtained in the compositional range of 0 ≤ x ≤ 0.25. The room temperature crystalline structure were refined by the Rietveld method using X-ray diffraction (XRD) data. The results of the crystal structure analysis indicate that the distance between the O3 and La2 atoms (O3-La2), increased with the amount of W dopant, and so does the distance between the O4 and O3 atoms (O4-O3). The electrical results reveal that La9.5Ge5.8W0.2O26.45 has the longest O3-La2 and O4-O3 distances (3.4838Å, 3.3376Å) in the solid solubility limit, with the highest electrical conductivity 0.0398 S/cm, at 800℃). These two results were combined in simulating the interstitial oxide migration path. The path way is a screw-like route around the c axis in three dimensional space and a sinusoid-like curve in the two dimensional ac plane. The activation energy is calculated from the Arrhenius plot, agreeing closely with the interstitial oxide mechanism.

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