La_(0.7)Ca_(0.3)Cr_(0.95)Zn_(0.05)O_(3-δ)性能表征及其薄膜制备

Characterization of La_(0.7)Ca_(0.3)Cr_(0.95)Zn_(0.05)O_(3-δ) and preparation of its film

采用甘氨酸-硝酸盐溶液燃烧法合成了D50为0.24μm的A位掺Ca、B位掺Zn的铬酸镧(La0.7Ca0.3Cr0.95Zn0.05-O3-δ,LCCZ)超细粉体,对其导电性、在还原气氛中的稳定性、与La0.8Sr0.2MnO3(LSM)阴极的兼容性以及热膨胀性能进行了研究。结果表明该材料在1 250℃煅烧5 h后相对致密度可达98%,烧结体在800℃时氧化和还原气氛中的电导率分别为54.6和2.36 S/cm,而且该材料在还原性气氛中稳定,与LSM化学兼容,与氧化钇稳定氧化锆(YSZ)热膨胀性能匹配。采用廉价的流延方式制备了厚度为30μm的LCCZ薄膜,有助于推动Ni-YSZ//YSZ//LSM型SOFC电堆的发展。

Super-fine powder of calcium and zinc substituted lanthanum chromite La0.7Ca0.3Cr0.95Zn0.05O3-δ（LCCZ） with an average particle size of 0.24 μm was synthesized by a combustion method.The electrical properties,stability in hydrogen,compatibility with LSM and thermal expansion behavior of LCCZ were investigated.The results show that the relative density of LCCZ compact is greater than 98% by sintering at 1 250 ℃ for 5 h in air.The electrical conductivities of sintered sample are up to 54.6 S/cm in air and 2.36 S/cm in hydrogen,respectively,at 800 ℃.The sample is stable at 800 ℃ in hydrogen and is compatible with LSM.The thermal expansion coefficient is close to that of YSZ and a 30μm LCCZ film is obtained by tape casting,which facilitates the development of Ni-YSZ//YSZ//LSM SOFC stack.