Effect of ions substitution with different radii on BO6 octahedral distortion of Bi3TiNbO9 high temperature piezoelectric ceramics

Bi2.99(Li0.5Sm0.5)0.01Ti0.985(W2/3M1/3)0.015NbO9 (abbreviated as B(LS)TNO-15WM, M is Al, Cr, and Sc) were prepared by solid state reaction sintering. The effects of B-site (W2/3M1/3)5+ complex-ion substitution on and their microstructure, piezoelectric properties, and electrical performance were systematically studied. B(LS)TNO-15WCr obtains the highest piezoelectric coefficient (d33). Through the calculation of XRD refined results, it is found that this is due to its greater distortion of BO6 octahedron. In this work, the possible sources of high performance of BTNO based ceramics doped at B-site are analyzed, which provides a certain theoretical support for future work.