凝胶注模工艺制备三维多孔Li1.3Al0.3Ti1.7（PO4）3固态电解质

Preparation of Three-Dimensional Porous Li1.3Al0.3Ti1.7（PO4）3 Solid-state Electrolyte by Gelcasting Method

三维多孔固态电解质是连续型复合电解质的骨架部分。采用共沉淀法制备Li1.3Al0.3Ti1.7(PO4)3固态电解质粉体,再通过凝胶注模工艺合成了Li1.3Al0.3Ti1.7(PO4)3多孔坯体,并在不同温度下烧结,比较了烧结体的物相组成、显微形貌、收缩率、孔隙率、电导率和激活能。结果表明:在900℃以上烧结,坯体发生明显的致密化,并且产生更多的杂相,其致密度升高而电导率降低。在800℃烧结的样品,孔隙率在50%以上,具有6.94×10–5 S/cm的电导率,激活能为0.27 eV。所得多孔坯具有较高的孔隙率和电导率,使其适合作为三维有机–无机复合固态电解质的陶瓷框架。

Three-dimensional(3 D)porous solid-state electrolyte is the skeleton of continuous-type composite electrolyte.To prepare the continuous 3 D skeleton,Li1.3Al0.3Ti1.7(PO4)3solid-state electrolyte powder was synthesized by a co-precipitation method.The 3 D porous Li1.3Al0.3Ti1.7(PO4)3was prepared via gelcasting and subsequent sintering at different temperatures.The phase composition,microstructure,shrinkage,porosity,conductivity and activation energy of the sintered samples were compared.The results show that the solid-state electrolyte sample sintered above 900℃densifies,and more impure phases appear,thus decreasing the conductivity as the density increases.The sample sintered at 800℃has a porosity of above 50%,a conductivity of 6.94×10–5 S/cm,and an activation energy of 0.27 eV.This solid-state electrolyte with a high porosity and a relatively high electrical conductivity can be used as a ceramic framework for 3 D organic–inorganic composite solid electrolytes.