Growth and piezoelectric properties of ferroelectric Bi2WO6 mono-domain crystals

A mono-domain crystal of Bismuth tungstate Bi2WO6, one of the bismuth layered structure ferroelectric (BLSF) compounds, is synthesized by a slow cooling method using lithium tetra-borate as the flux below the Curie temperature of 940 °C. Fifteen of seventeen independent tensor components of dielectric constant εij/ε0, piezoelectric constant dij and elastic compliance sij are determined. The dielectric constants, εij/ε0, were about 100, 70 and 70 for ij=11, 22 and 33 and the piezoelectric constants, d31 and d33 were −17 and 27 pC/N, respectively. These characteristics are consistent with those of BLSF grain-oriented ceramics. The resonance response revealed that the BWO crystals maintained the piezoelectricity up to 400 °C.