Phase-Driven Property Modulation in BiVO₄ Ceramics via Multi-ion Substitution for Next-Generation Wireless...

Area of Science:

• Materials Science
• Solid-State Chemistry
• Dielectric Ceramics

Background:

• Growing demand for high-performance wireless communication necessitates advanced dielectric materials.
• BiVO4-based ceramics are promising for microwave applications due to their thermal stability.

Purpose of the Study:

• Synthesize novel Bi1-4x(LaxNdxSmxEux)VO4 ceramics.
• Investigate the impact of multi-ion substitution on phase structure and dielectric properties.
• Evaluate their potential for ISM-band communication devices.

Main Methods:

• Conventional solid-state synthesis at low firing temperatures (740-860 °C).
• Structural characterization using X-ray diffraction, HRTEM, and Raman spectroscopy.
• Dielectric property analysis via microwave and far-infrared spectroscopy.

Main Results:

• Composition-driven phase transition from monoclinic scheelite to tetragonal zircon observed near x ≈ 0.075.
• Dielectric permittivity (εr) decreased from 66.98 to 19.85, while quality factor (Qf) increased from 7904 to 16240 GHz with increasing x.
• A near temperature-stable dielectric loss tangent (τf) of +8.42 ppm/°C achieved at x = 0.055.
• A microstrip patch antenna fabricated with x = 0.055 ceramic demonstrated excellent performance (return loss -22.5 dB, 98.8% radiation efficiency).

Conclusions:

• Controlling multi-ion substitution effectively tunes phase composition and dielectric performance in BiVO4 ceramics.
• The developed ceramics show significant potential for ISM-band communication and emerging wireless technologies.
• Low firing temperature synthesis offers a practical advantage for device fabrication.