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研究，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℃的導電率只有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，在前人的研究當中提出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， =1.36Å)離子半徑相近的鍶(CN=12， =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。
為了改進材料的緻密化行為，本研究以水熱法製程進行La0.7Sr0.3VO3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。

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. This kind of low conductivity made LaVO3 consider as an insulator. The vanadium atom in LaVO3 was a transition metal with 3d orbital. In preliminary studies the conductivity of lanthanum vanadate could be promoted by heterovalent doping. The state of valent electrons in the 3d orbital would change owing to heterovalent doping.

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.

La0.7Sr0.3VO3 synthesized by hydrothermal method showed a single perovskite phase when heat-treated at 800oC for 5h in the atmosphere containing 20%H2 and 80%Ar. On the contrary, temperature as high as 1100oC is needed in order to obtain a single-phase La0.7Sr0.3VO3 using solid state reaction. The temperature difference between the two processes was about 300oC. The particle size of hydrothermal powders with different hydrothermal time was about 230-290nm. The particle size of hydrothermal powder after reducing heat- treatment at 800oC has grown to 290-400nm. The beginning of densification temperature was estimated to be at 935oC for the sample prepared by hydrothermal method. However, the densification onset temperature of solid-state reacted sample began at 1176oC. The temperature of densification behavior was significantly reduced over 200oC. The enhanced reactivity of hydrothermally processed La0.7Sr0.3VO3 was rationalized by increasing surface area due to the nano-sized powder.

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