Microwave Dielectric Properties and Applications of (Bi 0.2 La 0.2 Nd 0.2 Sm 0.2 Gd 0.2 ) 2 MoO 6 High‐Entropy Ceramics

ABSTRACT Microwave dielectric materials are indispensable to wireless communications. However, achieving a balanced optimization of their three key parameters ( ε r , Q × f , τ f ) remains a significant challenge. In this study, a high‐entropy design strategy is adopted via the introduction of Nd 2 MoO 6 into the A‐site. Through a conventional solid‐state reaction method, a novel microwave dielectric ceramic, (Bi 0.2 La 0.2 Nd 0.2 Sm 0.2 Gd 0.2 ) 2 MoO 6 , applicable to low‐temperature co‐fired ceramic technology, was successfully synthesized. This ceramic crystallizes in the tetragonal crystal system with the space group I41/acd (142). Its microwave dielectric properties, microstructure, chemical bond characteristics, and application potential were systematically investigated. When sintered at 1000°C, the material achieves optimal comprehensive performance: ɛ r = 15.427, Q × f = 11,820 GHz, and τ f = −2.047 ppm/°C. Furthermore, sintering at 950°C enables the ceramic to exhibit excellent chemical compatibility with silver during co‐firing processes. Both the single dielectric resonator antenna and the 2×2 antenna array designed based on (Bi 0.2 La 0.2 Nd 0.2 Sm 0.2 Gd 0.2 ) 2 MoO 6 demonstrate high radiation efficiency (>96%) and gain values of 5.91 and 7.86 dBi. These findings indicate that this high‐entropy ceramics holds broad application prospects in high‐performance, low‐loss microwave integrated devices.