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La0.6Sr0.4Co1-yFeyO3钙钛矿复合氧化物的GNP法合成与导电性能 总被引:6,自引:2,他引:4
采用甘氨酸-硝酸盐(GNP)法合成出La0.6Sr0.4Co1-yFeyO3(y=0~1.0)体系复合氧化物,对合成产物的结构、烧结性能和导电性进行了表征.研究结果表明,不同n(Co)/n(Fe)比的合成粉料中形成菱形六面体钙钛矿结构,合成粉料的颗粒细小均匀.在室温~900℃范围内,La0.6Sr0.4CoO3(y=0)的电导率随温度的升高而单调降低,其它n(Co)/n(Fe)比的样品电导率随着温度升高到600℃附近时达到最大值.在低温段,La0.6Sr0.4Co1-yFeyO3体系的导电行为符合小极化子导电机制,导电活化能随n(Co)/n(Fe)比的降低而增大.与常规固相合成法相比,甘氨酸-硝酸盐法制备的La0.6Sr0.4Co1-yFeyO3具有更高的烧结活性和电导率. 相似文献
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SUN Junli JIAO Lifang LIU Li WEI Xin YANG Lin LIU Sichen YUAN Huatang WANG Yongmei 《中国化学》2009,27(5):863-867
溶胶凝胶法合成了层状的LiTiyV3-0.8yO8(y=0, 0.04, 0.06, 0.08)正极材料,这些材料因为掺杂Ti量的不同,而具有了不同的形貌特征(形状,粒径,比表面积)以及电化学性质(首次充放电容量, 循环容量等)。XRD,SEM, CV,及充放电测试对该正极材料的结构和电化学性能进行了表征,结果表明当y=0.04时,该正极材料拥有最高的首次放电容量(348.9mAhg-1)和最好的容量循环性能。 相似文献
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《Magnetic resonance in chemistry : MRC》2018,56(9):803-809
The local angular distortions Δθ are theoretically studied for the various Ni3+ centers in LiAlyCo1–yO2 at different Al concentrations (y = 0, 0.1, 0.5, and 0.8) based on the perturbation calculations of electron paramagnetic resonance g factors for a trigonally distorted octahedral 3d7 cluster with low spin (S = 1/2). Due to the Jahn–Teller effect, the [NiO6]9– clusters are found to experience the local angular distortions (Δθ ≈ 5°–9°) along the C3 axis. The variation trend of Δθ with y is in accordance with that of anisotropy (Δg = g|| − g⊥). As the substitutions can weaken bond strengths between transition metal and oxygen and the structural stability plays an important role in cathode performances, detailed investigations on the structural properties of the cathode materials LiAlyCo1–yO2 can be practically helpful to understand the performances of these materials. The oxy‐redox properties of LiAlyCo1–yO2 systems are comprehensible in the framework of Ni3+/Ni4+ couples, and the trigonally compressed octahedral [NiO6]9– clusters are applicable to the clarification of the electrochemical properties of lithium nickel oxide batteries. It appears that LiAl0.8Co0.2O2 with the largest Al concentration may correspond to the smallest distortion among the mixing systems. 相似文献
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