Abstract:W6+-doped SrBi8Ti7-x WxO27 (SBT-BIT-xW6+ ,x=0.00,0.02,0.04,0.06,0.08,0.10) inter-growth bismuth layered ceramics were prepared by a conventionalsolid-state method. Theeffectof W6+ doping on crystal structure, microstructure, dielectric, piezoelectric and ferroelectric properties of ceramics were systematically studied.
The results show that all the ceramics possess a single inter-growth bismuth layer-structured with m=3.5, and all ceramics have compact structures and are in good sinter condition. The Raman results show that the crystal structure is optimized, and the lattice distortion is reduced by W6+ doping. Donor doping can effectively reduce the oxygen vacancy concentration, greatly reduce the dielectric loss of ceramic samples, and significantly enhance the ferroelectric and piezoelectric properties of the samples. Optimizedpr operties is obtained with composition of x=0.08(d33=24.1pC/N, 2Pr=5.54μC/cm2,Tc=554℃), which exhibits excellent thermal stability and can retain 96.3% of their initial d33
values after annealing at 500 ℃ for 2h. All above results implying that this ceramic has potential application at high temperature.
Keywords: intergrowth structure; donor doping; microstructure; electrical properties; oxygen vacancy; SrBi4Ti4O15-Bi4Ti3O12