La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(0.2)O_(2.8)的电化学性质及其在SOFC中的应用  

Electrochemical Properties of La_(0.8)Sr_ (0.2)Ga_(0.8)Mg_(0.2)O_(2.8) Electrolyte and Its Application to SOFCs

作　　者：查少武[1] 李海滨[1] 夏长荣[1] 刘杏芹[1] 孟广耀[1] 

机构地区：[1]中国科学技术大学材料科学与工程系,合肥230026

出　　处：《高等学校化学学报》2003年第3期506-508,共3页Chemical Journal of Chinese Universities

基　　金：国家 8 63计划 (批准号 :2 0 0 1AA 32 30 90 );国家自然科学基金 (批准号 :2 0 0 719)资助

摘　　要：采用凝胶浇注法制备具有较高氧离子电导率的固体电解质 La0 .8Sr0 .2 Ga0 .8Mg0 .2 O2 .8粉料 .X射线衍射结果表明 ,于 1 4 0 0℃焙烧后即形成了钙钛矿结构 ,无杂相存在 .探讨了粉料压制坯体的致密化和导电性能在 1 4 5 0℃下与烧结时间的关系 ,发现烧结时间为 1 8h时其相对密度达 98.3 % ,而在 2 4 h的情况下 ,样品具有最佳的氧离子导电性 .采用 Ni-Ce0 .8Gd0 .2 O1.9作为阳极 ,La0 .8Sr0 .2 Ga0 .6 Ni0 .4 O2 .7作为阴极 ,组装了平板型固体氧化物燃料电池 (SOFC) .阳极和阴极分别通入含 3 % H2 O的氢气和空气 ,75 0℃时的开路电压为1 .0 4 V,最大输出功率密度 (P)达 2 5 2 m W/cm2 (U=0 .4 8V,J=5 2 5 m A/cm2 ) .Sr- and Mg-doped LaGaO_3(La_ 0.8Sr_ 0.2Ga_ 0.8Mg_ 0.2O_ 2.8) powders have been successfully synthesized from carbonate and oxides based on the principle of gelcasting. XRD patterns indicate the perovskite structure is formed without any second phases after sintering the powders at 1 400 ℃ for 6 h. The pellet sample was sintered to 98.3% of theoretical density at 1 450 ℃ for 18 h. The total electrical conductivity was greatly depended on the sintering time, and reached the maximum when the pellet was sintered at {1 450} ℃ for 24 h. Planar SOFC was constructed using Ni-Ce_ 0.8Gd_ 0.2O_ 1.9 and La_ 0.8Sr_ 0.2Ga_ 0.6Ni_ 0.4O_ 2.7 as the anode and cathode, respectively. When humidified hydrogen and air were introduced to the two electrodes, maximum power density of 252 mW/cm 2(U=0.48 V, J=525 mA/cm 2) was achieved with the open circuit voltage of 1.04 V at 750 ℃.

关 键 词：La0.8Sr0.2Ga0.8Mg0.2O2.8 电化学性质 SOFC 凝胶浇注法 固体氧化物燃料电池 

分 类 号：TM911.4[电气工程—电力电子与电力传动] O646.5[理学—物理化学]