NASICON-type Li_1.3Al_0.3Ti_1.7(PO₄)₃ ceramics with frequency dispersion effect and microwave absorption properties in 8.2–12.4 GHz

This work aimed to develop NASICON-type Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) ceramic as a new type of high-temperature microwave absorption material. LATP ceramics were prepared by traditional solid-state reaction with sintering temperature ranging from 950 to 1100 °C for phase, microstructure, conductivity, dielectric property, and microwave absorption property study. Moreover, the dielectric property and microwave absorption property of LATP ceramic and NASICON-type Na₃Zr₂Si₂PO₁₂ (NZSP) ceramic in our previous work were compared. Results showed that LATP ceramic sintered at 1050 °C exhibited the highest conductivity of 2.43 × 10^–4 S cm⁻¹ and optimal microwave absorption property. The minimum reflection loss (RL_min) was − 13.4 dB at 11.14 GHz and the bandwidth (RL < − 10 dB) was 2.27 GHz (9.63–11.90 GHz) in 2.2 mm. The values of complex permittivity of NZSP and LATP ceramics were similar. While the frequency dispersion effect only occurred in LATP ceramic, which resulted in its superior microwave absorption property over NZSP ceramic.