以釩系La1-xSrxVO3 方面的系統研究早期在低溫導電率及磁性已累積相當程度的成果，其中有SrVO3 當作甲烷及苯氧化的催化劑之研究，而La1-xSrxVO3 則以當作異丙醇分解的催化劑之用，近年來，氧化鍶摻雜鑭釩氧化物被發現在硫化氫以及甲烷的環境下可維持結構穩定和化學穩定性，當為固態氧化物燃料電池(SOFC)以沼氣當作燃料時，可作為抗腐蝕的電極材料。
具鈣鈦礦結構的氧化物LaVO3在純氫的氣氛下800℃的導電值只有0.689S/cm，為一絕緣體，LaVO3中的釩原子為過渡金屬，因其具有3d的價電子軌域，藉由異價摻雜的方式，可改變其中釩的電子組態會使得其導電率有所提升。
本研究選取與鑭(CN=12， 3+ La r =1.36Å)離子半徑相近的鍶(CN=12， Sr 2+ r =1.44Å)當作摻雜的離子，改變摻雜的量觀察氧化鍶摻雜對於LaVO3的晶體結構及導電率的影響。氧化鑭與氧化釩混合粉末於1100℃還原氣氛下煆燒5小時後，形成斜方相的鈣鈦礦結構。當氧化鍶的摻雜量達30%時，煆燒後試樣結構由斜方相變成立方相的鈣鈦礦結構。是由於氧化鍶的摻雜導致釩平均價數增加，藉釩離子平均半徑減小，減少釩氧八面體的distortion，使立方相得以穩定。
根據La1-xSrxVO3之XPS實驗的結果，當氧化鍶摻雜到鑭離子晶格位置時，會使得釩離子的價數發生改變，提高了四價釩以及五價釩等離子濃度，而多價數釩同時存在讓電子得以在三種價數釩之間躍遷(Hopping)使 La1-xSrxVO3的電子導電率得以提升，La0.7Sr0.3VO3在純氫下800℃導電率為188S/cm，而SrVO3則可達365S/cm。
當La1-xSrxVO3試樣從室溫加熱至1000℃時，以TMA (熱機械分析儀)量測與計算具鈣鈦礦結構的La1-xSrxVO3的膨脹係數，隨斯摻雜量增加從6.09×10-6變化至20×10-6之間，其中以La0.7Sr0.3VO3 (La0.7SV)的熱膨脹係數最為接近電解質釔安定氧化鋯(Yttria-stabilized zirconia，YSZ)的值。
本研究以水熱法製程進行La0.7Sr0.3VO3 (L0.7SV)粉末細化，於800℃含20%H2與80%Ar的環境中熱處理5小時可得具鈣鈦礦結構的單相，與固相法需1100℃的熱處理溫度相差約300℃。
從粒徑分析的結果顯示未經還原熱處理的顆粒大小約介於230-290nm，再經還原熱處理之後的顆粒大小則成長至290-400nm。奈米粉末的燒結曲線顯示在溫度約935℃時開始有收縮的行為，相較於固相反應製程的粉末，其收縮的行為則在1176℃時才開始出現。由於粉末奈米化的效應，提高了比表面積，使得顆粒與顆粒之間的反應活性提升，降低了燒結溫度。因此經水熱製程的試片在1500℃10小時燒結後的緻密程度高於固相法製程其孔隙率分別為3.55%及13.8%，其中水熱製程試片的晶粒大小約為2.033μm。
陽極材料與常用之電解質材料YSZ高溫穩定性則是利用L0.7SV/YSZ之混合粉末至於高溫爐中進行熱處理後分析，當L0.7SV /YSZ粉末於1100 oC還原氣氛下進行24小時熱處理後並無反應物生成，然而當La0.7SV-YSZ混合粉於1200 oC以上熱處理時，可發現有SrZrO3生成。
最後, 本研究以電解質支撐形式將多孔質La0.7SV被覆於YSZ上，進行IT-SOFC單電池測試。
當單電池在操作溫度850 oC，陽極端分別通入200之氫氣與甲烷氣體，陰極則是通入500sccm之氧氣進行測試，電池最大電力密度約為108mWcm-2與36mWcm-2

La1-xSrxVO3 system has received a lot of attention. Some researches of SrVO3 were about the catalytic of methane and benzene, and La1-xSrxVO3 was used as a catalytic property of isopropanol decomposition. Recently, crystal structure and chemical stability of La1-xSrxVO3 were found to be stable in the environment of hydrosulfide and methane. Such characteristics provided a new possibility of using syngas as fuel in Solid Oxide Fuel Cell (SOFC).
The conductivity of pure lanthanum vanadium oxide with perovskite structure was only 0.689S/cm in pure hydrogen atmosphere. LaVO3 was considered to be an insulator due to its low conductivity mentioned above. The most common method of increasing conductivity was by heterovalent doping. Conductive electrons or holes were created so the conductivity could be improved. In preliminary studies the state of valent electrons of vanadium atom in the 3d orbital would change by heterovalent doping. The effect of heterovalent doping would reflect on promoting the conductivity of lanthanum vanadate oxide.
In this study, the strontium ion was selected to substitute lanthanum ion due to the similarity in ionic radius. The addition of strontium ion was varied to observe the influence on crystal structure and conductivity. The powder mixture of lanthanum oxide, vanadium oxide and strontium oxide were calcined at 1100oC for 5h in the reducing atmosphere. The crystal structure of LaVO3 was orthorhombic which was confirmed by XRD analysis. With increasing amount of strontium doping up to 30% the crystal structure changed from orthorhombic to cubic structure. The doping of strontium oxide increased the average valent state of vanadium ion, and then the average radius of vanadium ion was suppressed. As a result, the distortion of V-O octahedral diminished, and then the cubic phase was stabilized.
According to XPS analysis when lanthanum ion was substituted by strontium ion the valence of vanadium ion changed to high valent state from trivalent to tetravalent or pentavalent state. Then the concentration of tetravalent and pentavalent ions increased with the increasing of strontium ion doping. The electrons may hop among three valent of vanadium ions, and this cause the enhanced conductivity of La1-xSrxVO3. The conductivity of La0.7Sr0.3VO3 and SrVO3 in pure hydrogen atmosphere was measured to be 188S/cm and 365S/cm, respectively.
The thermal expansion coefficient (TEC) of La1-xSrxVO3 was measured by TMA from room temperature to 1000oC. The TEC of La1-xSrxVO3 ranged from 6.09×10-6 to 20×10-6. TEC of La0.7Sr0.3O3 was found to be very close to that of YSZ.
The chemical reaction between these two materials in the temperature ranging from 1100 to 1400oC was examined by X-ray diffraction (XRD) analyses. No secondary phase was detected when the L0.7SV /YSZ powder mixture was heated at 1100oC. The reaction products of perovskite SrZrO3 were formed when the specimens were heated treatment at over 1200oC. The bonding energy between La-O (188kcal/mole) is stronger than Sr-O (83.6kcal/mole). So the La3+ ions diffused to YSZ lattice is not easily.
The material thermal stability of anode material against an electrolyte at an operating temperature plays an important role in the fuel cell’s performance. The synthesis and performance of L0.7SV/YSZ composites are investigated as alternative anodes for the direct utilization of methane in solid oxide fuel cells. For the performance testing, the maximum power density at 850 ◦C is 108 mWcm-2 with hydrogen and air flows, respectively.

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