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

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.