Giant Polarization and High Temperature Monoclinic Phase in a Lead-Free Perovskite of Bi(Zn0.5Ti0.5)O3-BiFeO3

Zhao Pan; Jun Chen; Runze Yu; Hajime Yamamoto; Yangchun Rong; Lei Hu; Qiang Li; Kun Lin; Li You; Kun Zhao; Longlong Fan; Yang Ren; Kenichi Kato; Masaki Azuma; Xianran Xing

doi:10.1021/acs.inorgchem.6b01661

Giant Polarization and High Temperature Monoclinic Phase in a Lead-Free Perovskite of Bi(Zn_0.5Ti_0.5)O₃-BiFeO₃

Inorg Chem. 2016 Oct 3;55(19):9513-9516. doi: 10.1021/acs.inorgchem.6b01661. Epub 2016 Sep 15.

Authors

Affiliations

¹ Materials and Structures Laboratory, Tokyo Institute of Technology , 4259 Nagatsuta, Midori, Yokohama 226-8503, Japan.
² X-ray Science Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
³ RIKEN SPring-8 Center , 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.

PMID: 27631595
DOI: 10.1021/acs.inorgchem.6b01661

Abstract

Lead-free piezoelectrics have attracted increasing attention because of the awareness of lead toxicity to the environment. Here, a new bismuth-based lead-free perovskite, (1 - x)Bi(Zn_0.5Ti_0.5)O₃-xBiFeO₃, has been synthesized via a high-pressure and high-temperature method. It exhibits interesting properties of giant polarization, morphotropic phase boundary (MPB), and monoclinic phase. In particular, large tetragonality (c/a = 1.228) and giant spontaneous polarization of 110 μC/cm² has been obtained in 0.6 Bi(Zn_0.5Ti_0.5)O₃-0.4BiFeO₃, which is much higher than most available lead-free materials and conventional Pb(Zr,Ti)O₃. MPB is clearly identified to be constituted of tetragonal and monoclinic phases at x = 0.5. Notably, a single monoclinic phase has been observed at x = 0.6, which exhibits an intriguing high-temperature property. The present results are helpful to explore new lead-free MPB systems in bismuth-based compounds.