(貴州師范學(xué)院 貴州省納米材料模擬與計(jì)算重點(diǎn)實(shí)驗(yàn)室，貴陽 550018)
摘 要: 本文采用溶液靜電紡絲的方法，制備了一種纖維結(jié)構(gòu)陰極材料La0.5Sr0.5CoO3-δ，系統(tǒng)研究了該陰極材料的結(jié)構(gòu)、熱穩(wěn)定性和電化學(xué)性能。結(jié)果表明：相對于常規(guī)粉末材料制備的普通顆粒結(jié)構(gòu)陰極，纖維結(jié)構(gòu)陰極的晶格熱穩(wěn)定性良好，孔隙分布更加均勻合理，電化學(xué)性能更加優(yōu)越。在800 ℃下，纖維結(jié)構(gòu)陰極的界面電阻低至0.035 Ω？cm2，對應(yīng)單電池的最大輸出功率為930 mW/cm2，表現(xiàn)出快速的氧還原反應(yīng)電極過程動力學(xué)；常規(guī)多孔結(jié)構(gòu)陰極的界面電阻為0.065 Ω？cm2，對應(yīng)單電池的最大輸出功率僅為750 mW/cm2；在電池的運(yùn)行過程中，纖維結(jié)構(gòu)陰極的電化學(xué)性能也較穩(wěn)定，在750 ℃和0.6 V恒電位載荷下運(yùn)行15 h后，電池的輸出功率從740 mW/cm2緩慢衰減到660 mW/cm2，表明極化電阻的加劇程度較小。
關(guān)鍵字: 固體氧化物燃料電池；陰極；電化學(xué)性能；纖維結(jié)構(gòu)
（Guizhou Provincial Key Laboratory of Computational Nano-Material Science, Guizhou Education University, Guiyang 550018, China）
Abstract:A fiber-structured La0.5Sr0.5CoO3-δ cathode was prepared via electrostatic spinning of solution, and the structure, thermal stability, and electrochemical performance of this fiber-structured cathode was systematically investigated. The results show that, compared with the common particle-structured cathode prepared from the plain powder material, this fiber-structured cathode reveals more favorable thermal stability of lattice, more rational pore distribution, and more advanced electrochemical performance. At 800 ℃, the area specific resistance with this fiber-structured cathode is as low as 0.035 Ω？cm2, and the maximum power density with the corresponding single-cell is 930 mW/cm2, showing the fast electrode kinetics of oxygen reduction reaction. Comparatively, the area specific resistance with the common particle-structured cathode is 0.065 Ω？cm2, and the maximum power density with the corresponding single-cell is only 750 mW/cm2. Moreover, in cell operation, the electrochemical performance of this fiber-structured cathode is also very stable, and the output power of cells under a constant loading voltage of 0.6 V at 750 ℃ drops slowly from 740 mW/cm2 to 660 mW/cm2 after 15 h of running, showing the slow worsening of area specific resistance.
Key words: solid oxide fuel cell; cathode material; electrochemical performance; fibrous structure
