甘氨酸-硝酸盐法合成GdBaCo2O5+δ阴极材料及其性能

摘要

GdBaCo2O5+δ(GBCO) powders were synthesized by the glycine-nitrate process (GNP) with different glycine/metal ratios (G/M) and characterized as cathode material for intermediate temperature solid oxide fuel cell(IT-SOFC). The effects of G/M ratios on the performance and properties of GBCO electrodes including the morphology, crystal structure, electrical conductivity and electrochemical properties were evaluated. The GBCO powder synthesized at G/M ratio of 3.0 (GBCO-3.0) showed the highest specific surface area. XRD results proved that the precursor powders calcined at 1000℃ for 5 h formed GBCO single-phase when the ratio of glycine to metal was in the range of 2.5-3.5. There were no chemical reaction occurred between the GBCO cathode and the Sm0.2Ce0.8O1.9 (SDC) electrolyte after calcination at HOOD. The electrical conductivities of all GBCO cathodes were over 100 S/cm at intermediate temperature (500-800℃). The GBCO-3.0 cathode calcined at 1050℃ exhibited the lowest polarization resistance (Rp) of 0.125 Ω·cm2 at 750℃%采用甘氨酸-硝酸盐法(GNP)制备中温固体氧化物燃料电池(IT-SOFC)GdBaCo2O5+δ(GBCO)阴极材料,探索甘氨酸与金属阳离子摩尔比(G/M)等合成条件对产物性能的影响,研究了GBCO的微观形貌、晶体结构、电导率和电化学性能.结果表明,GIM为3.0的阴极粉料(GBCO-3.0)颗粒细小均匀且比表面积大,G/M在2.5～3.5之间制备的粉料经1000℃煅烧5h可形成结晶度高的GBCO纯相.阴极材料GBCO与电解质材料Smo.2Ce0.8O1.9(SDC)在1100℃混合煅烧,未发生明显的化学反应.在500～800℃范围内,GBCO阴极的电导率均大于100S/em.1050℃煅烧的GBCO-3.0阴极的极化电阻(Rp)最小,750℃为0.125Ω·cm2.