Effects of ZrO2 additions on the dielectric properties of CaCu3Ti4O12

The dielectric spectra of CaCu3Ti4O12 is characterized by a large permittivity (εr>10000) with only a weak dependence on temperature over the temperature range 200–400 K. In this work, doping with 0.1–1.0 wt % ZrO2 has been shown to dramatically reduce the dielectric loss. At 0.5 wt % ZrO2,tanδ remains below 0.05 over the frequency range 50 Hz–30 kHz and is just 0.065 at 100 kHz. While there is some diminution of the permittivity (εr≈5000 at 10 kHz) Zr-doped ceramics, exhibited very little bias dependence (ΔC∕C0<1.0% up to 40 V). In summary, results suggest that ZrO2 doping is an effective method for maintaining a high permittivity and low loss over a broad range in temperature, bias, and frequency.