中溫固態氧化物燃料電池鑭鍶鈷鐵基複合陰極層之分析及電性研究

Abstract

本研究，選擇數種複合陰極材料,進行多層半電池(陰極/電解質)製備與介面電阻與極化電阻之分析，再進一步製備出全電池，測量其電能輸出。 電極材料利用共析出法，製備出不同粒徑大小之氧化釓添加氧化铈 (GDC) 球型粉體。另外，利用Pechini法製備GDC及LSCF粉體，以做為阻隔層，在鑭鍶鈷鐵陰極中，加入78nm~2.5um GDC粉體，以降低其陰極極化阻抗及防止晶粒粗化。在陰極複合材使用的則是鑭鍶鈷鐵(LSCF6428)，透過兩種合成法固態反應法與Pechini法均可成功合成高表面積出單相且成分均一之粉體。 最後，利用旋鍍法(spin coating) 製備出不同微結構之半電池，進行交流阻抗(AC-impedance)分析，透過單層至多層之陰極結構解析出各層之間之介面極化阻抗與接觸電阻。並使用氧化鎳/氧化鋯(NiO/YSZ)及四層陰極結構製備出單一陽極支撐全電池，其I-V量測結果約為362 mW/cm2。

This study, select the several composite cathode materials for multiple layered half-cell (cathode / electrolyte) fabrication and precede analysis of the interface resistance and polarization resistance, and then further fabricated a full single cell, measuring power output. Electrode material Gd2O3 doped cerium spherical powder with different particle sizes were synthesized by co-precipitation method, preparation of, add of cerium oxide (GDC). In addition, by using the Pechini method to synthesize GDC and LSCF powder as the barrier layer. With the addition of 78nm ~ 2.5 um GDC powder in the lanthanum strontium cobalt iron oxide (LSCF6428) cathode to reduce the cathodic polarization resistance and prevent the grain coarsening. The lanthanum strontium cobalt iron oxide (LSCF6428) was used for composite cathode material, the powder can be successfully synthesized with high surface area and with single phase and homogeneous composition by solid-state reaction method and the Pechini method. Finally, the half-cells fabricated by spin coating with different microstructure were taken in to measurement of AC-impedance. The interface polarization resistance and contact resistance were analyzed by the half-cells with single layer to multi-layer cathode structure. The optimized four layered cathode microstructure was also applied with the NiO/YSZ as anode material into the anode support single cell for I-V test, and the result of power density was 362 mW/cm2