近年由於環保意識的興起帶動一些新興的產業，例如:電動汽車，太陽能轉換器等，加上對於在高溫工作下使用的需求，例如:航太，石油天然氣探勘等，因此在高溫環境下使用的電容材料是有市場需求的；常見的電容材料鈦酸鋇 (BaTiO3) 由於受限於相變溫度，使這類電容只能在較低溫約200°C 以下的環境應用。根據科學家的研究，發現僅次於鈣鈦礦結構的第二大類介電材料鎢青銅結構具有可應用在高溫之下的潛力，因此本研究認為要研發出可在高溫下作使用的電容材料可從鎢青銅結構的材料下手。
本研究使用固態反應法合成 (Sr2-x-zCaxYz)Na(Nb5-zZrz)O15 、 Sr2Na(Nb5-zTaz)O15，藉由顯微結構、結晶結構、拉曼光譜分析、電性量測等方法，來探討鎢青銅結構中的鈮酸鍶鈉不同離子摻雜取代的性質之影響。實驗結果顯示，使用 1200°C 持溫 6 小時進行粉末煅燒，經過 X 光繞射分析下，成功合成出鎢青銅結構化合物，並無分析到第二相存在。在鈣、釔、鋯等量摻雜取代後，高溫介電峰的部分往低溫偏移且寬化的現象，有擴散介電行為。在減少鈣摻雜取代量時，小孔洞增加、緻密度下降，導致絕緣電阻率下降，在低溫段相對介電常數的部分，減少鈣摻雜取代量時，由於極性奈米區域的減少導致低溫段介電峰些微平坦化。在鉭摻雜取代下受到抑制晶粒成長的效果，不論是煅燒粉末顆粒還是陶瓷體晶粒大小都有較小的趨勢，在煅燒粉末與燒結陶瓷體的 X 光繞射結果都有發現到在 (2θ=45°-48°) 時繞射峰分裂，表示晶體結構從非中心對稱轉變為中心對稱，與相對介電常數對溫度結果圖相解釋則為隨鉭摻雜取代，結晶結構從 (P4bm) 轉變為 (P4/mbm) 導致極化量下降、相對介電常數值下降，高溫介電峰往低溫偏移，當摻雜取代量達等於 2 mol 時在室溫下呈現順電性。在所有成分點中，鈣、釔、鋯等量摻雜取代 5 mol% 時，由於晶粒大小較小、均勻，且顯微結構中沒有太多裂縫、孔洞，因此擁有最佳絕緣電阻率表現，平均絕緣電阻率為 46 GΩ·m 。

In this study, (Sr2-x-zCaxYz)Na(Nb5-zZrz)O15 and Sr2Na(Nb5-zTaz)O15 were synthesized by solid-state reaction method. The experimental results show that the powder was calcined at 1200°C for 6 hours. After X-ray diffraction analysis, the tungsten bronze structure compound was successfully synthesized, and no second phase was detected. After calcium, yttrium, and zirconium are doped and replaced, the part of the high-temperature dielectric peak shifts to the low temperature and broadens, showing a diffuse dielectric behavior. When reducing the calcium doping substitution amount, the small pores increase and the density decreases, decreasing the insulation resistivity. In the part of the relative permittivity of the low-temperature section, when the amount of calcium doping substitution is reduced, the dielectric peak of the low-temperature section is slightly flattened due to the reduction of the polar nanoregions (PNRs). Under the substitution of tantalum doping, due to the effect of inhibiting grain growth, both the calcined powder particles and the grain size of the ceramic body tend to be smaller. In the X-ray diffraction results of the calcined powder and the sintered ceramic body, it was found that the diffraction peak split at (2θ=45°-48°), indicating that the crystal structure changed from non-centrosymmetric to centrosymmetric. Interpretation of the relative permittivity vs. temperature results shows that, with the substitution of tantalum doping, the crystallographic structure shifts from (P4bm) to (P4/mbm) resulting in a decrease in polarization and a decrease in the relative permittivity value. When the tantalum doping substitution amount is equal to 2 mol, the high-temperature dielectric peak shifts significantly to the low temperature, showing paraelectricity at room temperature. In all composition points, when calcium, yttrium, and zirconium are doped to replace 5 mol%, due to the small and uniform grain size, and there are not too many cracks and holes in the microstructure, it has the best performance of insulation resistivity. The average insulation resistivity is 46 GΩ·m.

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