A NASICON-type Li_1.5Al_0.5Ti_1.5(PO₄)₃ (LATP) solid electrolyte was fabricated using a novel sol–gel approach with citric acid as a complex agent. An electrochemical impedance spectroscopy analysis shows that the ionic conductivity of the LATP solid electrolyte synthesized using the sol–gel route was low (8 × 10⁻⁵ S cm⁻¹ at 303 K), owing to its large grain boundary impedance. To improve the ionic conductivity of the LATP conducting ceramic, we incorporated Nb₂O₅ as a doping agent into the LATP solid electrolyte. The effects of Nb₂O₅ on the phase composition, microstructure, and ionic conductivity of the LATP solid electrolyte were investigated. The LATP conducting ceramic with an 8-wt% Nb₂O₅ doping exhibited the highest total ionic conductivity of 3.54 × 10⁻⁴ S cm⁻¹ at 303 K, relative density of 91.7%, and lowest activation energy of 0.271 eV. The fabricated LATP solid electrolyte doped with Nb₂O₅ is a promising material for electrochemical devices.

使用新颖的溶胶-凝胶法，以柠檬酸为络合剂，制备了NASICON型Li _1.5 Al _0.5 Ti _1.5（PO ₄）₃（LATP）固体电解质。电化学阻抗谱分析表明，由于其较大的晶界阻抗，使用溶胶-凝胶法合成的LATP固体电解质的离子电导率较低（在303 K时为8×10 ^-5  S cm ^-1）。为了提高LATP导电陶瓷的离子电导率，我们将Nb ₂ O ₅作为掺杂剂掺入LATP固体电解质中。Nb ₂ O _5的作用研究了LATP固体电解质的相组成，微观结构和离子电导率。掺杂了8 wt％Nb ₂ O ₅的LATP导电陶瓷在303 K时显示出最高的总离子电导率3.54×10 ^-4  S cm ^-1，相对密度为91.7％，最低的活化能为0.271 eV。制备的掺有Nb ₂ O _5的LATP固体电解质是一种有前途的电化学装置材料。