(Ce_(0.8)Sm_(0.2)O_(2-δ)/Y_2O_3:ZrO_2)_N超晶格电解质薄膜的制备及表征  

Preparation and characterization of the superlattice(Sm-doped ceria/yttria-stabilized zirconia)_N electrolyte film

作　　者：刘华艳[1] 范悦[1] 康振锋 许彦彬[1] 薄青瑞 丁铁柱[1] 

机构地区：[1]内蒙古大学物理科学与技术学院,呼和浩特010021

出　　处：《物理学报》2015年第23期243-248,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11264025)资助的课题~~

摘　　要：采用脉冲激光沉积技术(PLD),在MgO单晶基底上,依次沉积氧化钐掺杂的氧化铈(Ce_(0.8)Sm_(0.2)O_(2-δ),SDC)和钇稳定氧化锆(8 mol%Y_2O_3:ZrO_2,YSZ)制备了五种(SDC/YSZ)_N(N=3,5,10,20,30)超晶格电解质薄膜.利用X射线衍射(XRD)、高分辨透射电子显微镜(HR-TEM)和交流阻抗对其形貌、相结构和电学性能进行了表征.结果显示,(SDC/YSZ)_N超晶格电解质薄膜之间形成了明显的界面和较好的超晶格结构;薄膜表面颗粒生长均匀、致密、平滑,在薄膜的界面处没有元素相互扩散也未出现裂纹,外延生长良好;电导率随着(SDC/YSZ)_N超晶格电解质界面数的增加而增加,而活化能则随之减少,是较为理想的低温固体氧化物燃料电池电解质.As is well known,a solid oxide fuel cell（SOFC） is a device that can convert chemical energy directly into electrical energy.The possibility to grow thin films of oxide materials is of great importance in the development of SOFC.Recently,it is expected that oxide heterostructures,with almost ideal interfaces,should lead to the interesting artificial materials with some novel properties.So we have prepared superlattice electrolyte thin films.On the Mg O single-crystal substrates,multilayer epitaxial thin-film heterostructures of 20 mol% samarium-oxidedoped ceria（Ce0.8Sm0.2O2-δ,SDC） and 8 mol% yttria-stabilized zirconia（Y2O3： ZrO2YSZ） have been deposited in turn,using the pulsed laser deposition（PLD） technique.Five different superlattices（SDC/YSZ）N（N = 3,5,10,20,30） films are fabricated,keeping the total thickness constant（300 nm）,but with a different number of hetero-interfaces.The choice of coupling SDC and YSZ aims to have both layers in the superlattices made of oxygen-ion conductors with compatible crystallographic features.On one hand,we have to remove any potential contribution of the deposition substrate to the total conductivity,and the superlattices may be grown on {110}-oriented MgO single-crystalline wafers.On the other hand,the YSZ electrolyte film requires that the temperature should be higher,and SDC as the electrolyte leakage; both should be combined with each other,so as to have complementary advantages.In this way,not only the temperature of SOFCs is reduced,but also the leakage avoided.Because YSZ and SDC both belong to cubic fluorite structure and have similar lattice parameters,the lattice constant of YSZ is 5.14 ？,and the lattice constant of SDC is 5.44 ？.Compatible crystal properties,oxygen ion conductivity,and great matching defects can lead to a semi-coherent interface between the ZrO2 and CeO2 layers.The interface effect is obvious.X-ray diffraction（XRD）,high-resolution transmission electron microscopy（HR-TEM） and AC impedance mearurements are used

关 键 词：固体氧化物燃料电池 超晶格电解质薄膜 界面 双分子层 

分 类 号：TB383.2[一般工业技术—材料科学与工程]