2020. 02-present: Associate Professor, School of Mathematics and Physics, University of Science and Technology Beijing (USTB), China; 2014. 09-2020. 02: PhD, Department of Physical Chemistry, University of Science and Technology Beijing (USTB), China; 2018. 10-2019. 10: Visiting Scholar, Department Physics, Central Michigan University, USA;

1. We analyzed the intrinsic and extrinsic piezoelectric contributions in lead and lead-free perovskite-type piezoelectrics. In lead-based high performance piezoelectric ceramics, we found the monoclinic polarization rotation and structure transformation play an important role in achieving large piezoelectric response. 2. We resolved the complex polar structure of PbZrO3–based antiferroelectric perovskites, and revealed its structure evolution under applied electric field by using advanced diffraction/ total scattering techniques.

1-2 Master students per year

(1) Hui Liu, Longlong Fan, Shengdong Sun, Kun Lin, Yang Ren, Xiaoli Tan, Xianran Xing, Jun Chen*, Electric-field-induced structure and domain texture evolution in PbZrO3-based antiferroelectric by in-situ high-energy synchrotron x-ray diffraction, Acta Mater. 2020, 184, 41-49. (2) Hui Liu, Jun Chen*, Houbing Huang, Longlong Fan, Yang Ren, Zhao Pan, Jinxia Deng, Long-Qing Chen, and Xianran Xing, Role of reversible phase transformation for strong piezoelectric performance at morphotropic phase boundary, Phys. Rev. Lett. 2018, 120, 055501. (3) Hui Liu, Jun Chen*, Longlong Fan, Yang Ren, Zhao Pan, K. V. Lalitha, Jürgen Rödel, and Xianran Xing, Critical role of monoclinic polarization rotation in high-performance perovskite piezoelectric materials, Phys. Rev. Lett. 2017, 119, 017601. (4) Hui Liu#, Zhengyang Zhou#, Yi Qiu#, Botao Gao, Shengdong Sun, Kun Lin, Lei Ding, Qiang Li, Yili Cao, Yang Ren, Junliang Sun*, Xianran Xing, Jun Chen*, An intriguing intermediate state as a bridge between antiferroelectric and ferroelectric perovskites, Mater. Horiz. 2020, 7, 1912-1918. (5) Hui Liu, Jun Chen*, Longlong Fan, Yang Ren, Lei Hu, Fangmin Guo, Jinxia Deng, Xianran Xing, Structural evidence for strong coupling between polarization rotation and lattice strain in monoclinic relaxor ferroelectrics, Chem. Mater. 2017, 29, 5767-5771. (6) Hui Liu#, Houbing Huang#, Longlong Fan, Yang Ren, Hua Zhou, Long-Qing Chen, Jun Chen*, Xianran Xing, Synergy between phase transformation and domain switching in two morphotropic phase boundary ferroelectrics, Phy. Rev. Mater. 2018, 1, 111403. (7) Hui Liu, Jun Chen*, Yang Ren, Linxing Zhang, Zhao Pan, Longlong Fan, Xianran Xing, Large photovoltage and controllable photovoltaic effect in PbTiO3-Bi(Ni2/3+xNb1/3-x)O3-δ ferroelectrics, Adv. Electron. Mater. 2015, 1, 1400051. (8) Hui Liu, Jun Chen*, Xingxing Jiang, Zhao Pan, Linxing Zhang, Yangchun Rong, Zheshuai Lin, Xianran Xing, Controllable negative thermal expansion, ferroelectric and semiconducting properties in PbTiO3–Bi(Co2/3Nb1/3)O3 solid solutions, J. Mater. Chem. C 2017, 5, 931. (9) Shengdong Sun, Yueyun Zhang, Longlong Fan, Shiqing Deng, Botao Gao, Yang Ren, Hui Liu*, Jun Chen*. Role of tetragonal distortion on domain switching and lattice strain of piezoelectrics by in-situ synchrotron diffraction. Scripta Mater. 2021, 194, 113627. (10) Hui Liu#, Shengdong Sun#, Zhao Pan, Longlong Fan, Yang Ren, Xianran Xing, Jun Chen, Multiple contributions to electrostrain in high performance PbTiO3-Bi(Ni1/2Hf1/2)O3 piezoceramics triggered by phase transformation. J. Eur. Ceram. Soc. 2019, 39, 5277-5284. (11) Lu Wang, Shengdong Sun, Huajie Luo, Yang Ren, Hui Liu*, Xianran Xing, Jun Chen*, Boosted piezoelectricity with excellent thermal stability in tetragonal NaNbO3-based ceramics, J. Mater. Chem. A 2021, 9, 2367-2374. (12) Jianbo Zhang, Hui Liu*, Shengdong Sun, Ye Liu, Yueyun Zhang, He Qi, Shiqing Deng, Jun Chen. Crystal structure and actuation mechanisms in morphotropic phase boundary Pb(Zn1/3Nb2/3)O3-Pb(Zr1/2Ti1/2)O3 piezoelectric ceramic, J Am Ceram Soc. 2021, 104, 2621–2627. (13) Yueyun Zhang, Hui Liu*, Shengdong Sun, Shiqing Deng, Jun Chen*. Systematic study of structure and piezoelectric properties of Pb(Ni1/3Nb2/3)O3-PbTiO3 by in situ synchrotron diffraction, J Am Ceram Soc. 2021, 104, 604–612. (14) Huajie Luo#, Hui Liu#, Shiqing Deng, Shuxian Hu, Lu Wang, Botao Gao, Shengdong Sun, Yang Ren, Lijie Qiao, Jun Chen*. Acta Mater. 2021, 208, 116711.

2021 postgraduate: Zheng Sun