Large reduction of dielectric losses of CaCu 3 Ti 4 O 12 ceramics via air quenching

Abstract Although the CaCu 3 Ti 4 O 12 ceramics have colossal dielectric constants, their relative high dielectric losses are one of the limiting factors for commercial applications. Various doping elements and additive compounds have been extensively used to reduce their dielectric losses with only limited success. Instead of using such doping elements, this work shows that a facile air quenching technique can considerably reduce the dielectric losses of the CaCu 3 Ti 4 O 12 ceramics over a wide frequency range. In the meantime, their colossal dielectric constants can be simultaneously enhanced. It was found that the dielectric loss of the air-quenched CaCu 3 Ti 4 O 12 ceramics is as low as 0.03 at 12 kHz, and the dielectric constant is over 1×10 4 across the frequency range up to 1 MHz.