TY - JOUR
T1 - Bismuth Oxychalcogenides
T2 - A New Class of Ferroelectric/Ferroelastic Materials with Ultra High Mobility
AU - Wu, Menghao
AU - Zeng, Xiao Cheng
N1 - Funding Information:
†School of Physics and National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China ‡Department of Chemistry and Nebraska Center for Materials and Nanoscience, University of Nebraska−Lincoln, Lincoln, Nebraska 68588, United States §Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei, Anhui 230026, China
Funding Information:
M.W. is supported by the National Natural Science Foundation of China (Nos. 21573084). X.C.Z. is supported by the US National Science Foundation through the Nebraska Materials Research Science and Engineering Center (MRSEC) (grant No. DMR-1420645), a Qian-ren B (One Thousand Talents Plan B) summer research fund from USTC, and by a State Key R&D Fund of China (2016YFA0200604) to USTC. We also thank Shanghai Supercomputing Center for providing computational resources.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/10/11
Y1 - 2017/10/11
N2 - Atomically thin Bi2O2Se has been recently synthesized, and it possesses ultrahigh mobility (Nat. Nanotechnol. 2017, 12, 530; Nano Lett. 2017, 17, 3021). Herein, we show first-principles evidence that Bi2O2Se and a related class of bismuth oxychalcogenides, such as Bi2O2S and Bi2O2Te, not only are novel semiconductors with ultrahigh mobility but also possess previously unreported ferroelectricity/ferroelasticity. Such a unique combination of semiconducting with ferroelectric/ferroelastic properties enables bismuth oxychalcogenides to potentially meet a great challenge, that is, integration of room-temperature functional nonvolatile memories into future nanocircuits. Specifically, we predict that bulk Bi2O2S is both ferroelastic and antiferroelectric and that a thin film with odd number of layers can even be multiferroic with nonzero in-plane polarization, and this polarization can be switchable via ferroelasticity. Moreover, Bi2O2Te possesses intrinsic out-of-plane ferroelectricity, while Bi2O2Se possesses piezoelectricity and ferroelectricity upon an in-plane strain. The in-plane strain on Bi2O2Se can induce giant polarizations (56.1 μC/cm2 upon 4.1% strain) with the piezoelectric coefficient being about 35 times higher than that of MoS2 monolayer. The in-plane strain can also enhance the bandgap or even convert indirect to direct bandgap beyond a critical value. The good match among the lattice constants of bismuth oxychalcogenides is also desirable, rendering the epitaxial growth of heterostructure devices free of fabrication issues related to lattice mismatch, thereby allowing high-quality bismuth oxychalcogenide heterostructures tailored by design for a variety of applications.
AB - Atomically thin Bi2O2Se has been recently synthesized, and it possesses ultrahigh mobility (Nat. Nanotechnol. 2017, 12, 530; Nano Lett. 2017, 17, 3021). Herein, we show first-principles evidence that Bi2O2Se and a related class of bismuth oxychalcogenides, such as Bi2O2S and Bi2O2Te, not only are novel semiconductors with ultrahigh mobility but also possess previously unreported ferroelectricity/ferroelasticity. Such a unique combination of semiconducting with ferroelectric/ferroelastic properties enables bismuth oxychalcogenides to potentially meet a great challenge, that is, integration of room-temperature functional nonvolatile memories into future nanocircuits. Specifically, we predict that bulk Bi2O2S is both ferroelastic and antiferroelectric and that a thin film with odd number of layers can even be multiferroic with nonzero in-plane polarization, and this polarization can be switchable via ferroelasticity. Moreover, Bi2O2Te possesses intrinsic out-of-plane ferroelectricity, while Bi2O2Se possesses piezoelectricity and ferroelectricity upon an in-plane strain. The in-plane strain on Bi2O2Se can induce giant polarizations (56.1 μC/cm2 upon 4.1% strain) with the piezoelectric coefficient being about 35 times higher than that of MoS2 monolayer. The in-plane strain can also enhance the bandgap or even convert indirect to direct bandgap beyond a critical value. The good match among the lattice constants of bismuth oxychalcogenides is also desirable, rendering the epitaxial growth of heterostructure devices free of fabrication issues related to lattice mismatch, thereby allowing high-quality bismuth oxychalcogenide heterostructures tailored by design for a variety of applications.
KW - Ferroelectrics
KW - ferroelastics
KW - high-mobility bismuth oxychalcogenides
KW - piezoelectrics
KW - vertical polarization
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U2 - 10.1021/acs.nanolett.7b03020
DO - 10.1021/acs.nanolett.7b03020
M3 - Article
C2 - 28929772
AN - SCOPUS:85031278573
SN - 1530-6984
VL - 17
SP - 6309
EP - 6314
JO - Nano Letters
JF - Nano Letters
IS - 10
ER -