Determination of chemical ordering in the complex perovskite Pb(Cd1/3Nb2/3)O3

Caiyan Wang; Zhengqian Fu; Nan Zhang; Marek Paściak; Jian Zhuang; Zenghui Liu; Wei Ren; Zuo-Guang Ye

doi:10.1107/S2052252518013805

Determination of chemical ordering in the complex perovskite Pb(Cd_1/3Nb_2/3)O₃

IUCrJ. 2018 Oct 24;5(Pt 6):808-815. doi: 10.1107/S2052252518013805. eCollection 2018 Nov 1.

Authors

Caiyan Wang¹, Zhengqian Fu², Nan Zhang¹, Marek Paściak³, Jian Zhuang¹, Zenghui Liu¹, Wei Ren¹, Zuo-Guang Ye^{4

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Affiliations

¹ Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education and International Center for Dielectric Research, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.
² Analysis and Testing Center for Inorganic Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, People's Republic of China.
³ Institute of Physics, The Academy of Sciences of the Czech Republic, Na Slovance 2, Prague 182 21, Czech Republic.
⁴ Department of Chemistry and 4D LABS, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.

Abstract

Pure-phase Pb(Cd_1/3Nb_2/3)O₃ (PCN) single crystals and ceramics with a complex perovskite structure are synthesized for the first time. The local chemical ordering in PCN has been investigated by X-ray diffraction (including diffuse scattering) and Cs-corrected transmission electron microscopy experiments. It is concluded that the PCN samples have large coherent chemical ordering regions that even extend to the long range, and the ordering model is consistent with β-type chemical ordered regions. The antiphase domain boundaries were also observed. Two dielectric anomaly peaks were found in these two types of samples, one of which indicates possible relaxor behaviour. The novel structure of the completely ordered regions and its relationship with the electrical properties make PCN a unique material for the fundamental understanding of chemically substituted perovskites.

Keywords: atomic resolution EDS; chemical ordering; dielectric permittivity; diffuse scattering; electron microscopy; perovskites; relaxors.

Grants and funding

This work was funded by National Natural Science Foundation of China grant 61604123 to Nan Zhang. Fundamental Research Funds for the Central Universities of China grant . the ‘111 Project’ of China grant B14040 to Nan Zhang. Czech Science Foundation grant 15-04121S to Marek Paściak. US Office of Naval Research grants N00014-12-1-1045 and N00014-16-1-3106. Natural Sciences and Engineering Research Council of Canada grant 201773 to Zuo-guang Ye.