Probing ferroelectricity in Zr/Nb substituted BaTiO3-relaxors by piezoresponse force microscopy

For lead replacement in established Pb-based relaxor ferroelectric materials, substituted barium titanate is among the most promising candidates. The ceramic samples investigated in this study are B-site-substituted, with Zr or Nb partially replacing the central Ti ion in the perovskite lattice. Although these two material systems have been macroscopically well characterized by various techniques, local information on the ferroelectric domain structure is still missing. In this work, we probe the domain structure and local switchability across various compositions and temperatures using piezoresponse force microscopy. The results reveal that even though long-range ferroelectric order is effectively suppressed with increasing substitution, temporal stabilization of domains within a limited volume is still possible, indicating the presence of highly unstable polar nanoregions.