Defect dipoles inducing the larger piezoelectric properties in BaBi_4Ti_(4-x)(Cu_(0.5)W_(0.5))_XO_(15) ceramics

摘要

BaBi_4Ti_(4-x)(Cu_(0.5)W_(0.5))_XO_(15) ceramics with Cu~(2+) and W~(6+) co-substitution for the B-site Ti~(4+) were prepared by using the solid-state reaction process. It was desirable that piezoelectric properties of the BaBi_4Ti_(4-x)(Cu_(0.5)W_(0.5))_XO_(15) ceramics could be improved by inducing the larger lattice distortion with the oxygen vacancy defects neutralized and restrained. Results of the X-ray diffraction analysis confirmed that crystal cell parameter c decreased obviously with the increase in the crystal cell parameter a. Curie temperature, resistivity, and piezoelectric properties of the BBT ceramics are improved by the copper and tungsten modification. The maximum value of piezoelectric coefficient (～30 pC/N) can be obtained in the BaBi_4Ti_(4-x)(Cu_(0.5)W_(0.5))_XO_(15) ceramics.