Low-temperature microwave reaction sintering of ZnTiNb2O8 ceramics via two processing routes: Phase evolution, densification, and microwave dielectric properties
Year: 2026
Type: article
Abstract: ZnTiNb 2 O 8 microwave dielectric ceramics were synthesized through two processing routes and rapidly fabricated via microwave reaction sintering with a soaking time of only 30 min, yielding excellent dielectric performance. In the first route, ZnO, Nb 2 O 5 , and TiO 2 (in a 1:1:1 molar ratio) were high-energy ball-milled (ZNT) and sintered at 925–1025 °C. In the second route, ZnNb 2 O 6 was first formed from ZnO and Nb 2 O 5 , then milled with nano-TiO 2 (ZN–T) and sintered at 900–1000 °C. The lower optimal sintering temperature of the ZN–T route is attributed to the shorter reaction pathway provided by pre-synthesized ZnNb 2 O 6 and the more favorable densification behavior of this route compared with the direct oxide-mixing (ZNT) route. In addition, the finer particle size of the ZN–T precursor powders increases the driving force for sintering and provides shorter diffusion distances, thereby facilitating mass transport and promoting densification at lower temperatures. Phase evolution, densification behavior, microstructure, and dielectric properties were systematically examined. X-ray diffraction (XRD) and Raman spectroscopy confirmed a single-phase ixiolite structure. High relative densities of up to 99.45% were achieved, with optimal densification at 1000 °C for ZNT and 975 °C for ZN–T. ZN–T ceramics exhibited improved overall microwave dielectric performance, with ε r = 35.43, Q×f = 53,900 GHz, and τ f = −64.80 ppm °C -1 , whereas ZNT ceramics exhibited ε r = 35.95, Q×f = 51,800 GHz, and τ f = −66.60 ppm °C -1 .
Source: Journal of Alloys and Compounds
Institutions: University of Oulu, Tarbiat Modares University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,660
OpenAlex ID: W7204729321