燃烧法制备磷灰石型碱土掺杂硅酸镧电解质（英文）

Synthesis of Apatite-Type LSO Electrolyte Doped Alkali Earth by Urea-Nitrate Combustion

采用尿素-硝酸盐燃烧法,在较低温度下制备较高纯度无杂质相的碱土掺杂磷灰石型La_(9.33)M_x(SiO_4)_6O_(2+δ)电解质.通过XRD、SEM、交流阻抗测试,对样品的结构、形貌及电导性能进行研究.结果表明,燃烧合成的无定形电解质粉体,在800℃煅烧12h后,具有P63/m磷灰石型晶体结构;掺杂对LSO烧结体微观产生一定的影响,烧结体的结构和形貌随x值的变化而变化.此外,LSO烧结体具有良好的电阻可逆性和稳定性.适量的掺杂可有效提高LSO的离子电导率,过量的掺杂反而会降低离子电导率,最佳掺杂摩尔分数为0.2.而随着碱土金属阳离子半径增大,掺杂效果也越来越好.

The urea-nitrate combustion method was introduced to prepare high purity La9.33Mx （SiO4）602＋δ （M are St,Ca and Mg） conductor at low-temperature. The as-prepared samples were inves- tigated by XRD, FT-IR, SEM and EIS. The results showed that the powders transformed into P63/m apa- tire-type after burning at 800℃ for 12 h. Obvious effects of alkali earth doping amount on the microcos- mic appearance of si.ntered La9.33Mx （SiO4）602＋δ was observed,and the crystal structures altered with the different doping content. In addition , La9.33Mx （SiO4）602＋δ sintered body possessed good resistance reversibility and stability. The conductivity was improved efficiently with the proper amount of alkali earth oxide, and the optimal doping content was 0.2. Under the same doping content, the ionic conductivity was enhanced as the radius of alkali earth cationic increased （St2＋ 〉Ca2＋ 〉Mg2＋ ）.