High-Temperature Monoclinic Cc Phase with Reduced c/a Ratio in Bi-based Perovskite Compound Bi2ZnTi1-xMnxO6

Runze Yu; Narumi Matsuda; Ken Tominaga; Keisuke Shimizu; Hajime Hojo; Yuki Sakai; Hajime Yamamoto; Kengo Oka; Masaki Azuma

doi:10.1021/acs.inorgchem.6b00618

High-Temperature Monoclinic Cc Phase with Reduced c/a Ratio in Bi-based Perovskite Compound Bi2ZnTi1-xMnxO6

Inorg Chem. 2016 Jun 20;55(12):6124-9. doi: 10.1021/acs.inorgchem.6b00618. Epub 2016 Jun 2.

Authors

Runze Yu¹, Narumi Matsuda¹, Ken Tominaga¹, Keisuke Shimizu¹, Hajime Hojo¹, Yuki Sakai², Hajime Yamamoto¹, Kengo Oka³, Masaki Azuma¹

Affiliations

¹ Materials and Structures Laboratory, Tokyo Institute of Technology , 4259 Nagatsuta, Midori, Yokohama, 226-8503, Japan.
² Kanagawa Academy of Science and Technology, KSP , 3-2-1 Sakado, Takatsu-ku, Kawasaki City, Kanagawa 213-0012, Japan.
³ Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University , 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.

PMID: 27254112
DOI: 10.1021/acs.inorgchem.6b00618

Abstract

Monoclinic phases with Cm, Pm, and Cc space groups are indispensable to understand the high performance of electromechanical properties at the morphotropic phase boundary (MPB) of lead-based perovskite oxides Pb(ZrxTi1-x)O3 (PZT), [Pb(Mg1/3Nb2/3)O3]1-x-(PbTiO3)x (PMN-PT), and [Pb(Zn1/3Nb2/3)O3]1-x-(PbTiO3)x (PZN-PT). Here, a nearly single monoclinic phase with space group Cc was observed in the Bi-based lead-free perovskite compound Bi2ZnTi1-xMnxO6 at x = 0.4. This phase was the same as the low-temperature phase of the MPB composition of PZT but existed at a much higher temperature. Despite the reduced pseudo c/a ratio of 1.065, which is the same as that of PbTiO3 at room temperature, ionic model calculation based on the Rietveld refinement data indicated the polarization of Bi2ZnTi0.6Mn0.4O6 is 95.8 μC/cm(2). The tilting and significant anisotropic distortion of the octahedron were found to cause the c/a ratio to reduce. Accordingly, the effective piezoelectric constant d33 of Bi2ZnTi0.6Mn0.4O6 thin film was found to be 12 pm/V.