Sb + Lu co-doped TiO2 ceramics with ultralow loss, high permittivity, and excellent DC bias voltage stability

Abstract

Dielectric materials with large dielectric constants are increasingly used in electronics. In this study, dense (Sb0.5Lu0.5)xTi1-xO2 ceramics with strong electron-pinning clusters were prepared using a solid-state reaction. (Sb0.5Lu0.5)0.99Ti0.01O2 exhibited a giant dielectric constant of 1.51 × 104 and an ultralow dielectric loss of 0.004 at room temperature (RT). This ceramic also exhibited excellent frequency, temperature, and DC bias stabilities (RT–250 °C, 20 Hz–5 MHz, 0–32 V) owing to the high grain boundary resistance and strong electron-pinning effect. XPS, impedance spectroscopy, and relaxation behavior analysis revealed that electron-pinning, internal barrier layer, and electrode effects resulted in excellent dielectric behavior. This study demonstrates that the construction of defect clusters with strong electron-pinning effects is an effective method for obtaining giant dielectric ceramics with ultralow loss and temperature/DC bias stability.