Raman spectra and microwave dielectric properties of Na5Tm1 − x(Y1/3Yb2/3)x(MoO4)4 ceramics with ultra-low sintering temperature
Year: 2025
Type: article
Abstract: The Na 5 Tm 1 − x (Y 1/3 Yb 2/3 ) x (MoO 4 ) 4 ceramics (x=0-0.18) were successfully synthesized via the solid-state reaction method. XRD analysis revealed that they possessed a single-phase tetragonal scheelite structure belonging to the space group I4₁/a(88). SEM analysis demonstrated that the samples sintered at 600 °C exhibited a dense microstructure, with a relative density as high as 94.9% and an average grain size ranging from 2.172 μm to 2.424 μm. The relative density serves as an external factor influencing ε r and Q×f, while τ f is related to bond valence. The ionicity of the Tm-O bond, and the lattice energy and bond energy of the Mo-O bond are the intrinsic factors determining ε r , Q×f, and τ f , respectively. Raman spectroscopy provided an intuitive characterization of the vibrational properties of the [MoO 4 ] 2− tetrahedra within the ceramics. Although the pure phase Na₅Tm(MoO 4 ) 4 ceramic exhibited optimal dielectric properties (ε r =8.025, Q×f=18,967 GHz, and τ f = -101 ppm/°C) at 625 °C, the Na 5 Tm 0.91 Y 0.03 Yb 0.06 (MoO 4 ) 4 ceramic sintered at 600 °C demonstrated superior dielectric properties (ε r =7.82, Q×f=34,752 GHz, and τ f = -71.9 ppm/°C).
Source: Scientific Reports
Authors: Yuan-Bin Chen, Siyi Xiong
Institution: Zhaoqing University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,690
OpenAlex ID: W4407870262