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Wang T, Xue W, Yang H, Zhang Y, Cheng S, Fan Z, Li RW, Zhou P, Xu X. Robust Ferrimagnetism and Ferroelectricity in 2D ɛ-Fe 2O 3 Semiconductor with Ultrahigh Ordering Temperature. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2311041. [PMID: 39007252 DOI: 10.1002/adma.202311041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Revised: 06/06/2024] [Indexed: 07/16/2024]
Abstract
2D single-phase multiferroic materials with the coexistence of electric and spin polarization offer a tantalizing potential for high-density multilevel data storage. One of the current limitations for application is the scarcity of the materials, especially those combine ferromagnetism and ferroelectricity at high temperatures. Here, robust ferrimagnetism and ferroelectricity in 2D ɛ-Fe2O3 samples with both single-crystalline and polycrystalline form are demonstrated. Interestingly, the polycrystalline nanosheets also exhibit easily switchable ferroelectric polarizations comparable to that of single crystals. The existence of grain boundary does not hinder the switching and retention of ferroelectric polarization. Furthermore, the ɛ-Fe2O3 nanosheets show ferrimagnetic and ferroelectric Curie temperatures up to 800 K, which reaches record highs in 2D single-phase multiferroic materials. This work provides important progress in the exploration of 2D high-temperature single-phase multiferroics for potentially compact high-temperature information nanodevices.
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Affiliation(s)
- Tao Wang
- Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Taiyuan, 030031, China
| | - Wuhong Xue
- Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Taiyuan, 030031, China
| | - Huali Yang
- CAS Key Laboratory of Magnetic Materials and Devices & Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China
| | - Yongzhao Zhang
- Institute of Quantum Materials and Physics, Henan Academy of Science, Zhengzhou, 450046, China
| | - Shaobo Cheng
- Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material Physics, School of Physics and Microelectronics, Zhengzhou University, Zhengzhou, 450000, China
| | - Zhiwei Fan
- Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Taiyuan, 030031, China
| | - Run-Wei Li
- CAS Key Laboratory of Magnetic Materials and Devices & Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China
| | - Peng Zhou
- ASIC & System State Key Lab School of Microelectronics, Fudan University, Shanghai, 200433, China
| | - Xiaohong Xu
- Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Taiyuan, 030031, China
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2
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Spellberg JL, Kodaimati L, Joshi PP, Mirzajani N, Liang L, King SB. Electronic structure orientation as a map of in-plane antiferroelectricity in β'-In 2Se 3. SCIENCE ADVANCES 2024; 10:eado2136. [PMID: 38875325 PMCID: PMC11177895 DOI: 10.1126/sciadv.ado2136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 05/10/2024] [Indexed: 06/16/2024]
Abstract
Antiferroelectric (AFE) materials are excellent candidates for sensors, capacitors, and data storage due to their electrical switchability and high-energy storage capacity. However, imaging the nanoscale landscape of AFE domains is notoriously inaccessible, which has hindered development and intentional tuning of AFE materials. Here, we demonstrate that polarization-dependent photoemission electron microscopy can resolve the arrangement and orientation of in-plane AFE domains on the nanoscale, despite the absence of a net lattice polarization. Through direct determination of electronic transition orientations and analysis of domain boundary constraints, we establish that antiferroelectricity in β'-In2Se3 is a robust property from the scale of tens of nanometers to tens of micrometers. Ultimately, the method for imaging AFE domain organization presented here opens the door to investigations of the influence of domain formation and orientation on charge transport and dynamics.
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Affiliation(s)
- Joseph L Spellberg
- Department of Chemistry, University of Chicago, Chicago, IL 60637, USA
- James Franck Institute, University of Chicago, Chicago, IL 60637, USA
| | - Lina Kodaimati
- Department of Chemistry, University of Chicago, Chicago, IL 60637, USA
| | - Prakriti P Joshi
- James Franck Institute, University of Chicago, Chicago, IL 60637, USA
| | - Nasim Mirzajani
- Department of Chemistry, University of Chicago, Chicago, IL 60637, USA
- James Franck Institute, University of Chicago, Chicago, IL 60637, USA
| | - Liangbo Liang
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Sarah B King
- Department of Chemistry, University of Chicago, Chicago, IL 60637, USA
- James Franck Institute, University of Chicago, Chicago, IL 60637, USA
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3
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Li S, Wang F, Wang Y, Yang J, Wang X, Zhan X, He J, Wang Z. Van der Waals Ferroelectrics: Theories, Materials, and Device Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2301472. [PMID: 37363893 DOI: 10.1002/adma.202301472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 06/19/2023] [Indexed: 06/28/2023]
Abstract
In recent years, an increasing number of 2D van der Waals (vdW) materials are theory-predicted or laboratory-validated to possess in-plane (IP) and/or out-of-plane (OOP) spontaneous ferroelectric polarization. Due to their dangling-bond-free surfaces, interlayer charge coupling, robust polarization, tunable energy band structures, and compatibility with silicon-based technologies, vdW ferroelectric materials exhibit great promise in ferroelectric memories, neuromorphic computing, nanogenerators, photovoltaic devices, spintronic devices, and so on. Here, the very recent advances in the field of vdW ferroelectrics (FEs) are reviewed. First, theories of ferroelectricity are briefly discussed. Then, a comprehensive summary of the non-stacking vdW ferroelectric materials is provided based on their crystal structures and the emerging sliding ferroelectrics. In addition, their potential applications in various branches/frontier fields are enumerated, with a focus on artificial intelligence. Finally, the challenges and development prospects of vdW ferroelectrics are discussed.
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Affiliation(s)
- Shuhui Li
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Feng Wang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Yanrong Wang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Jia Yang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Xinyuan Wang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Xueying Zhan
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Jun He
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China
- Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan, 430072, P. R. China
| | - Zhenxing Wang
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, P. R. China
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4
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Lau G, Li Y, Zhang Y, Lin W. Reveal long-lived hot electrons in 2D indium selenide and ferroelectric-regulated carrier dynamics of InSe/α-In2Se3/InSe heterostructure. J Chem Phys 2024; 160:124701. [PMID: 38516977 DOI: 10.1063/5.0200098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 03/11/2024] [Indexed: 03/23/2024] Open
Abstract
As typical representatives of group III chalcogenides, InSe, α-In2Se3, and β'-In2Se3 have drawn considerable interest in the domain of photoelectrochemistry. However, the microscopic mechanisms of carrier dynamics in these systems remain largely unexplored. In this work, we first reveal that hot electrons in the three systems have different cooling rate stages and long-lived hot electrons, through the utilization of density functional theory calculations and nonadiabatic molecular dynamics simulations. Furthermore, the ferroelectric polarization of α-In2Se3 weakens the nonadiabatic coupling of the nonradioactive recombination, successfully competing with the narrow bandgap and slow dephasing process, and achieving both high optical absorption efficiency and long carrier lifetime. In addition, we demonstrate that the ferroelectric polarization of α-In2Se3 not only enables the formation of the double type-II band alignment in the InSe/α-In2Se3/InSe heterostructure, with the top and bottom InSe sublayers acting as acceptors and donors, respectively, but also eliminates the hindrance of the built-in electric field at the interface, facilitating an ultrafast interlayer carrier transfer in the heterojunction. This work establishes an atomic mechanism of carrier dynamics in InSe, α-In2Se3, and β'-In2Se3 and the regulatory role of the ferroelectric polarization on the charge carrier dynamics, providing a guideline for the design of photoelectronic materials.
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Affiliation(s)
- Guanghua Lau
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou 350108, People's Republic of China
| | - Yi Li
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou 350108, People's Republic of China
| | - Yongfan Zhang
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou 350108, People's Republic of China
- Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Xiamen, Fujian 361005, People's Republic of China
| | - Wei Lin
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou 350108, People's Republic of China
- Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Xiamen, Fujian 361005, People's Republic of China
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5
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Wang JL, Zhao YF, Xu W, Zheng JD, Shao YP, Tong WY, Duan CG. Nanotube ferroelectric tunnel junctions with an ultrahigh tunneling electroresistance ratio. MATERIALS HORIZONS 2024; 11:1325-1333. [PMID: 38174937 DOI: 10.1039/d3mh02006a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Low-dimensional ferroelectric tunnel junctions are appealing for the realization of nanoscale nonvolatile memory devices due to their inherent advantages of device miniaturization. Those based on current mechanisms have limitations, including low tunneling electroresistance (TER) effects and complex heterostructures. Here, we introduce an entirely new TER mechanism to construct a nanotube ferroelectric tunnel junction with ferroelectric nanotubes as the tunneling region. When rolling a ferroelectric monolayer into a nanotube, due to the coexistence of its intrinsic ferroelectric polarization with the flexoelectric polarization induced by bending, a metal-insulator transition occurs depending on the radiative polarization states. For the pristine monolayer, its out-of-plane polarization is tunable by an in-plane electric field, and the conducting states of the ferroelectric nanotube can thus be tuned between metallic and insulating states via axial electric means. Using α-In2Se3 as an example, our first-principles density functional theory calculations and nonequilibrium Green's function formalism confirm the feasibility of the TER mechanism and indicate an ultrahigh TER ratio that exceeds 9.9 × 1010% of the proposed nanotube ferroelectric tunnel junctions. Our findings provide a promising approach based on simple homogeneous structures for high density ferroelectric microelectric devices with excellent ON/OFF performance.
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Affiliation(s)
- Jiu-Long Wang
- Key Laboratory of Polar Materials and Devices (MOE), Ministry of Education, Department of Electronics, East China Normal University, Shanghai, 200241, China.
- Shanghai Center of Brain-inspired Intelligent Materials and Devices, East China Normal University, Shanghai 200241, China
| | - Yi-Feng Zhao
- Key Laboratory of Polar Materials and Devices (MOE), Ministry of Education, Department of Electronics, East China Normal University, Shanghai, 200241, China.
- Shanghai Center of Brain-inspired Intelligent Materials and Devices, East China Normal University, Shanghai 200241, China
| | - Wen Xu
- Key Laboratory of Polar Materials and Devices (MOE), Ministry of Education, Department of Electronics, East China Normal University, Shanghai, 200241, China.
- Shanghai Center of Brain-inspired Intelligent Materials and Devices, East China Normal University, Shanghai 200241, China
| | - Jun-Ding Zheng
- Key Laboratory of Polar Materials and Devices (MOE), Ministry of Education, Department of Electronics, East China Normal University, Shanghai, 200241, China.
- Shanghai Center of Brain-inspired Intelligent Materials and Devices, East China Normal University, Shanghai 200241, China
| | - Ya-Ping Shao
- Key Laboratory of Polar Materials and Devices (MOE), Ministry of Education, Department of Electronics, East China Normal University, Shanghai, 200241, China.
- Shanghai Center of Brain-inspired Intelligent Materials and Devices, East China Normal University, Shanghai 200241, China
| | - Wen-Yi Tong
- Key Laboratory of Polar Materials and Devices (MOE), Ministry of Education, Department of Electronics, East China Normal University, Shanghai, 200241, China.
- Shanghai Center of Brain-inspired Intelligent Materials and Devices, East China Normal University, Shanghai 200241, China
| | - Chun-Gang Duan
- Key Laboratory of Polar Materials and Devices (MOE), Ministry of Education, Department of Electronics, East China Normal University, Shanghai, 200241, China.
- Shanghai Center of Brain-inspired Intelligent Materials and Devices, East China Normal University, Shanghai 200241, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University Taiyuan, Shanxi 030006, China
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6
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Deng T, Gao Z, Qiu P, Zhou Z, Ming C, Liu Z, Li Z, Yang S, Wei TR, Wang G, Chen L, Shi X. High Thermoelectric Power Factors in Plastic/Ductile Bulk SnSe 2 -Based Crystals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2304219. [PMID: 38011362 DOI: 10.1002/adma.202304219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 10/16/2023] [Indexed: 11/29/2023]
Abstract
The recently discovered plastic/ductile inorganic thermoelectric (TE) materials open a new avenue for the fabrication of high-efficiently flexible TE devices, which can utilize the small temperature difference between human body and environment to generate electricity. However, the maximum power factor (PF) of current plastic/ductile TE materials is usually around or less than 10 µW cm-1 K-2 , much lower than the classic brittle TE materials. In this work, a record-high PF of 18.0 µW cm-1 K-2 at 375 K in plastic/ductile bulk SnSe2 -based crystals is reported, superior to all the plastic inorganic TE materials and flexible organic TE materials reported before. The origin of such high PF is from the modulation of material's stacking forms and polymorph crystal structures via simultaneously doping Cl/Br at Se-site and intercalating Cu inside the van der Waals gap, leading to the significantly enhanced carrier concentrations and mobilities. An in-plane fully flexible TE device made of the plastic/ductile SnSe2 -based crystals is successfully developed to show a record-high normalized maximum power density to 0.18 W m-1 under a temperature difference of 30 K. This work indicates that the plastic/ductile material can realize high TE power factor to achieve large output electric power density in flexible TE technology.
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Affiliation(s)
- Tingting Deng
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Zhiqiang Gao
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Pengfei Qiu
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhengyang Zhou
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
- Beijing National Laboratory for Molecular Sciences, Beijing, 100190, China
| | - Chen Ming
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Zhiping Liu
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Zhi Li
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Shiqi Yang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Tian-Ran Wei
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Genshui Wang
- School of Chemistry and Materials Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
| | - Lidong Chen
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xun Shi
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
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7
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Wang L, Zhou X, Su M, Zhang Y, Li R, Zhang R, Wu X, Wu Z, Wong WPD, Xu QH, He Q, Loh KP. In-Plane Ferrielectric Order in van der Waals β'-In 2Se 3. ACS NANO 2024; 18:809-818. [PMID: 38108268 DOI: 10.1021/acsnano.3c09250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
van der Waals ferroic materials exhibit rich potential for implementing future generation functional devices. Among these, layered β'-In2Se3 has fascinated researchers with its complex superlattice and domain structures. As opposed to ferroelectric α-In2Se3, the understanding of β'-In2Se3 ferroic properties remains unclear because ferroelectric, antiferroelectric, and ferroelastic characteristics have been separately reported in this material. To develop useful applications, it is necessary to understand the microscopic structural properties and their correlation with macroscopic device characteristics. Herein, using scanning transmission electron microscopy (STEM), we observed that the arrangement of dipoles deviates from the ideal double antiparallel antiferroelectric character due to competition between antiferroelectric and ferroelectric structural ordering. By virtue of second-harmonic generation, four-dimensional STEM, and in-plane piezoresponse force microscopy, the long-range inversion-breaking symmetry, uncompensated local polarization, and net polarization domains are unambiguously verified, revealing β'-In2Se3 as an in-plane ferrielectric layered material. Additionally, our device study reveals analogous resistive switching behaviors of different types owing to polarization switching, defect migration, and defect-induced charge trapping/detrapping processes.
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Affiliation(s)
- Lin Wang
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
- School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Xin Zhou
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Mengyao Su
- Department of Materials Science and Engineering, National University of Singapore, Singapore 117574, Singapore
| | - Yishu Zhang
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Runlai Li
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Rongrong Zhang
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Xiao Wu
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Zhenyue Wu
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Walter P D Wong
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Qing-Hua Xu
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
| | - Qian He
- Department of Materials Science and Engineering, National University of Singapore, Singapore 117574, Singapore
| | - Kian Ping Loh
- Department of Chemistry, National University of Singapore, Singapore 117543, Singapore
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8
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Io WF, Pang SY, Wong LW, Zhao Y, Ding R, Mao J, Zhao Y, Guo F, Yuan S, Zhao J, Yi J, Hao J. Direct observation of intrinsic room-temperature ferroelectricity in 2D layered CuCrP 2S 6. Nat Commun 2023; 14:7304. [PMID: 37951934 PMCID: PMC10640637 DOI: 10.1038/s41467-023-43097-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 10/31/2023] [Indexed: 11/14/2023] Open
Abstract
Multiferroic materials have ignited enormous interest owing to their co-existence of ferroelectricity and ferromagnetism, which hold substantial promise for advanced device applications. However, the size effect, dangling bonds, and interface effect in traditional multiferroics severely hinder their potential in nanoscale device applications. Recent theoretical and experimental studies have evidenced the possibility of realizing two-dimensional (2D) multiferroicity in van der Waals (vdW) layered CuCrP2S6. However, the incorporation of magnetic Cr ions in the ferroelectric framework leads to antiferroelectric and antiferromagnetic orderings, while macroscopic spontaneous polarization is always absent. Herein, we report the direct observation of robust out-of-plane ferroelectricity in 2D vdW CuCrP2S6 at room temperature with a comprehensive investigation. Modification of the ferroelectric polarization states in 2D CuCrP2S6 nanoflakes is experimentally demonstrated. Moreover, external electric field-induced polarization switching and hysteresis loops are obtained in CuCrP2S6 down to ~2.6 nm (4 layers). By using atomically resolved scanning transmission electron microscopy, we unveil the origin of the emerged room-temperature ferroelectricity in 2D CuCrP2S6. Our work can facilitate the development of multifunctional nanodevices and provide important insights into the nature of ferroelectric ordering of this 2D vdW material.
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Affiliation(s)
- Weng Fu Io
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
| | - Sin -Yi Pang
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
| | - Lok Wing Wong
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
| | - Yuqian Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
| | - Ran Ding
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
| | - Jianfeng Mao
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
- The Hong Kong Polytechnic University Shenzhen Research Institute, 518057, Shenzhen, P.R. China
| | - Yifei Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
| | - Feng Guo
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
- The Hong Kong Polytechnic University Shenzhen Research Institute, 518057, Shenzhen, P.R. China
| | - Shuoguo Yuan
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
| | - Jiong Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China
| | - Jiabao Yi
- Global Innovative Centre for Advanced Nanomaterials, College of Engineering, Science and Environment, The University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Jianhua Hao
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, P.R. China.
- The Hong Kong Polytechnic University Shenzhen Research Institute, 518057, Shenzhen, P.R. China.
- Photonics Research Institute, The Hong Kong Polytechnic University, Hong Kong, P.R. China.
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9
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Shi C, Mao N, Zhang K, Zhang T, Chiu MH, Ashen K, Wang B, Tang X, Guo G, Lei S, Chen L, Cao Y, Qian X, Kong J, Han Y. Domain-dependent strain and stacking in two-dimensional van der Waals ferroelectrics. Nat Commun 2023; 14:7168. [PMID: 37935672 PMCID: PMC10630342 DOI: 10.1038/s41467-023-42947-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 10/27/2023] [Indexed: 11/09/2023] Open
Abstract
Van der Waals (vdW) ferroelectrics have attracted significant attention for their potential in next-generation nano-electronics. Two-dimensional (2D) group-IV monochalcogenides have emerged as a promising candidate due to their strong room temperature in-plane polarization down to a monolayer limit. However, their polarization is strongly coupled with the lattice strain and stacking orders, which impact their electronic properties. Here, we utilize four-dimensional scanning transmission electron microscopy (4D-STEM) to simultaneously probe the in-plane strain and out-of-plane stacking in vdW SnSe. Specifically, we observe large lattice strain up to 4% with a gradient across ~50 nm to compensate lattice mismatch at domain walls, mitigating defects initiation. Additionally, we discover the unusual ferroelectric-to-antiferroelectric domain walls stabilized by vdW force and may lead to anisotropic nonlinear optical responses. Our findings provide a comprehensive understanding of in-plane and out-of-plane structures affecting domain properties in vdW SnSe, laying the foundation for domain wall engineering in vdW ferroelectrics.
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Affiliation(s)
- Chuqiao Shi
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX, 77005, USA
| | - Nannan Mao
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Kena Zhang
- Departments of Materials Science and Engineering, University of Texas at Arlington, Arlington, TX, USA
| | - Tianyi Zhang
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ming-Hui Chiu
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Kenna Ashen
- Departments of Materials Science and Engineering, Texas A&M University, College Station, TX, USA
| | - Bo Wang
- Materials Research Institute and Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Xiuyu Tang
- Departments of Materials Science and Engineering, Texas A&M University, College Station, TX, USA
| | - Galio Guo
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX, 77005, USA
| | - Shiming Lei
- Department of Physics, Rice University, Houston, TX, 77005, USA
| | - Longqing Chen
- Materials Research Institute and Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Ye Cao
- Departments of Materials Science and Engineering, University of Texas at Arlington, Arlington, TX, USA
| | - Xiaofeng Qian
- Departments of Materials Science and Engineering, Texas A&M University, College Station, TX, USA
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX, USA
- Department of Physics and Astronomy, Texas A&M University, College Station, TX, USA
| | - Jing Kong
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yimo Han
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX, 77005, USA.
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10
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Man P, Huang L, Zhao J, Ly TH. Ferroic Phases in Two-Dimensional Materials. Chem Rev 2023; 123:10990-11046. [PMID: 37672768 DOI: 10.1021/acs.chemrev.3c00170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/08/2023]
Abstract
Two-dimensional (2D) ferroics, namely ferroelectric, ferromagnetic, and ferroelastic materials, are attracting rising interest due to their fascinating physical properties and promising functional applications. A variety of 2D ferroic phases, as well as 2D multiferroics and the novel 2D ferrovalleytronics/ferrotoroidics, have been recently predicted by theory, even down to the single atomic layers. Meanwhile, some of them have already been experimentally verified. In addition to the intrinsic 2D ferroics, appropriate stacking, doping, and defects can also artificially regulate the ferroic phases of 2D materials. Correspondingly, ferroic ordering in 2D materials exhibits enormous potential for future high density memory devices, energy conversion devices, and sensing devices, among other applications. In this paper, the recent research progresses on 2D ferroic phases are comprehensively reviewed, with emphasis on chemistry and structural origin of the ferroic properties. In addition, the promising applications of the 2D ferroics for information storage, optoelectronics, and sensing are also briefly discussed. Finally, we envisioned a few possible pathways for the future 2D ferroics research and development. This comprehensive overview on the 2D ferroic phases can provide an atlas for this field and facilitate further exploration of the intriguing new materials and physical phenomena, which will generate tremendous impact on future functional materials and devices.
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Affiliation(s)
- Ping Man
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, P. R. China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, P. R. China
| | - Lingli Huang
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, P. R. China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, P. R. China
| | - Jiong Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong 999077, P. R. China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, P. R. China
| | - Thuc Hue Ly
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, P. R. China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, P. R. China
- Department of Chemistry and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong 999077, P. R. China
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11
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Wang H, Wen Y, Zeng H, Xiong Z, Tu Y, Zhu H, Cheng R, Yin L, Jiang J, Zhai B, Liu C, Shan C, He J. 2D Ferroic Materials for Nonvolatile Memory Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023:e2305044. [PMID: 37486859 DOI: 10.1002/adma.202305044] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 07/21/2023] [Indexed: 07/26/2023]
Abstract
The emerging nonvolatile memory technologies based on ferroic materials are promising for producing high-speed, low-power, and high-density memory in the field of integrated circuits. Long-range ferroic orders observed in 2D materials have triggered extensive research interest in 2D magnets, 2D ferroelectrics, 2D multiferroics, and their device applications. Devices based on 2D ferroic materials and heterostructures with an atomically smooth interface and ultrathin thickness have exhibited impressive properties and significant potential for developing advanced nonvolatile memory. In this context, a systematic review of emergent 2D ferroic materials is conducted here, emphasizing their recent research on nonvolatile memory applications, with a view to proposing brighter prospects for 2D magnetic materials, 2D ferroelectric materials, 2D multiferroic materials, and their relevant devices.
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Affiliation(s)
- Hao Wang
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Yao Wen
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Hui Zeng
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Ziren Xiong
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Yangyuan Tu
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Hao Zhu
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Ruiqing Cheng
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Lei Yin
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Jian Jiang
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Baoxing Zhai
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Chuansheng Liu
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
| | - Chongxin Shan
- Henan Key Laboratory of Diamond Optoelectronic Materials and Devices, Key Laboratory of Material Physics, Ministry of Education, School of Physics, Zhengzhou University, Zhengzhou, 450052, China
| | - Jun He
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan, 430072, China
- Hubei Luojia Laboratory, Wuhan, 430079, China
- Wuhan Institute of Quantum Technology, Wuhan, 430206, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100190, China
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12
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Wu J, Ye Y, Jian J, Yao X, Li J, Tang B, Ma H, Wei M, Li W, Lin H, Li L. Reversible Thermally Driven Phase Change of Layered In 2Se 3 for Integrated Photonics. NANO LETTERS 2023. [PMID: 37405904 DOI: 10.1021/acs.nanolett.3c01247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
Abstract
Two-dimensional In2Se3, an unconventional phase-change material, has drawn considerable attention for polymorphic phase transitions and electronic device applications. However, its reversible thermally driven phase transitions and potential use in photonic devices have yet to be explored. In this study, we observe the thermally driven reversible phase transitions between α and β' phases with the assistance of local strain from surface wrinkles and ripples, as well as reversible phase changes within the β phase family. These transitions lead to changes in the refractive index and other optoelectronic properties with minimal optical loss at telecommunication bands, which are crucial in integrated photonic applications such as postfabrication phase trimming. Additionally, multilayer β'-In2Se3 working as a transparent microheater proves to be a viable option for efficient thermo-optic modulation. This prototype design for layered In2Se3 offers immense potential for integrated photonics and paves the way for multilevel, nonvolatile optical memory applications.
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Affiliation(s)
- Jianghong Wu
- Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province, School of Engineering, Westlake University, Hangzhou 310030, People's Republic of China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou 310024, People's Republic of China
| | - Yuting Ye
- Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province, School of Engineering, Westlake University, Hangzhou 310030, People's Republic of China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou 310024, People's Republic of China
| | - Jialing Jian
- Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province, School of Engineering, Westlake University, Hangzhou 310030, People's Republic of China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou 310024, People's Republic of China
| | - Xiaoping Yao
- Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province, School of Engineering, Westlake University, Hangzhou 310030, People's Republic of China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou 310024, People's Republic of China
| | - Junying Li
- State Key Laboratory of Modern Optical Instrumentation, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Bo Tang
- Institute of Microelectronics, Chinese Academic Society, Beijing 100029, People's Republic of China
| | - Hui Ma
- State Key Laboratory of Modern Optical Instrumentation, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Maoliang Wei
- State Key Laboratory of Modern Optical Instrumentation, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Wenbin Li
- Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province, School of Engineering, Westlake University, Hangzhou 310030, People's Republic of China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou 310024, People's Republic of China
| | - Hongtao Lin
- State Key Laboratory of Modern Optical Instrumentation, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Lan Li
- Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province, School of Engineering, Westlake University, Hangzhou 310030, People's Republic of China
- Institute of Advanced Technology, Westlake Institute for Advanced Study, Hangzhou 310024, People's Republic of China
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13
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Zhou S, Liao L, Chen J, Yu Y, Lv Z, Yang M, Yao B, Zhang S, Peng G, Huang Z, Liu Y, Qi X, Wang G. Periodic Ferroelectric Stripe Domains in α-In 2Se 3 Nanoflakes Grown via Reverse-Flow Chemical Vapor Deposition. ACS APPLIED MATERIALS & INTERFACES 2023; 15:23613-23622. [PMID: 37149900 DOI: 10.1021/acsami.3c01886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The two-dimensional (2D) layered semiconductor α-In2Se3 has aroused great interest in atomic-scale ferroelectric transistors, artificial synapses, and nonvolatile memory devices due to its distinguished 2D ferroelectric properties. We have synthesized α-In2Se3 nanosheets with rare in-plane ferroelectric stripe domains at room temperature on mica substrates using a reverse flow chemical vapor deposition (RFCVD) method and optimized growth parameters. This stripe domain contrast is found to be strongly correlated to the stacking of layers, and the interrelated out-of-plane (OOP) and in-plane (IP) polarization can be manipulated by mapping the artificial domain structure. The acquisition of amplitude and phase hysteresis loops confirms the OOP polarization ferroelectric property. The emergence of striped domains enriches the variety of the ferroelectric structure types and novel properties of 2D In2Se3. This work paves a new way for the controllable growth of van der Waals ferroelectrics and facilitates the development of novel ferroelectric memory device applications.
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Affiliation(s)
- Suyuan Zhou
- Hunan Key Laboratory for Micro-Nano Energy Materials and Devices, School of Physics and Optoelectronic, Xiangtan University, Xiangtan 411105, China
- Department of Physics, College of Sciences, National University of Defense Technology, Changsha 410073, China
| | - Luocheng Liao
- Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education, School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
| | - Jiahao Chen
- Department of Physics, College of Sciences, National University of Defense Technology, Changsha 410073, China
| | - Yayun Yu
- Department of Physics, College of Sciences, National University of Defense Technology, Changsha 410073, China
| | - Zhiquan Lv
- Department of Physics, College of Sciences, National University of Defense Technology, Changsha 410073, China
| | - Ming Yang
- Department of Physics, College of Sciences, National University of Defense Technology, Changsha 410073, China
| | - Bowen Yao
- Hunan Key Laboratory for Micro-Nano Energy Materials and Devices, School of Physics and Optoelectronic, Xiangtan University, Xiangtan 411105, China
- Department of Physics, College of Sciences, National University of Defense Technology, Changsha 410073, China
| | - Sen Zhang
- Department of Physics, College of Sciences, National University of Defense Technology, Changsha 410073, China
| | - Gang Peng
- Department of Physics, College of Sciences, National University of Defense Technology, Changsha 410073, China
| | - Zongyu Huang
- Hunan Key Laboratory for Micro-Nano Energy Materials and Devices, School of Physics and Optoelectronic, Xiangtan University, Xiangtan 411105, China
| | - Yunya Liu
- Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education, School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
| | - Xiang Qi
- Hunan Key Laboratory for Micro-Nano Energy Materials and Devices, School of Physics and Optoelectronic, Xiangtan University, Xiangtan 411105, China
| | - Guang Wang
- Department of Physics, College of Sciences, National University of Defense Technology, Changsha 410073, China
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14
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Meng Q, Yu F, Liu G, Zong J, Tian Q, Wang K, Qiu X, Wang C, Xi X, Zhang Y. Thickness-Dependent Evolutions of Surface Reconstruction and Band Structures in Epitaxial β-In2Se3 Thin Films. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13091533. [PMID: 37177078 PMCID: PMC10180126 DOI: 10.3390/nano13091533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 04/29/2023] [Accepted: 04/29/2023] [Indexed: 05/15/2023]
Abstract
Ferroelectric materials have received great attention in the field of data storage, benefiting from their exotic transport properties. Among these materials, the two-dimensional (2D) In2Se3 has been of particular interest because of its ability to exhibit both in-plane and out-of-plane ferroelectricity. In this article, we realized the molecular beam epitaxial (MBE) growth of β-In2Se3 films on bilayer graphene (BLG) substrates with precisely controlled thickness. Combining in situ scanning tunneling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES) measurements, we found that the four-monolayer β-In2Se3 is a semiconductor with a (9 × 1) reconstructed superlattice. In contrast, the monolayer β-In2Se3/BLG heterostructure does not show any surface reconstruction due to the interfacial interaction and moiré superlattice, which instead results in a folding Dirac cone at the center of the Brillouin zone. In addition, we found that the band gap of In2Se3 film decreases after potassium doping on its surface, and the valence band maximum also shifts in momentum after surface potassium doping. The successful growth of high-quality β-In2Se3 thin films would be a new platform for studying the 2D ferroelectric heterostructures and devices. The experimental results on the surface reconstruction and band structures also provide important information on the quantum confinement and interfacial effects in the epitaxial β-In2Se3 films.
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Affiliation(s)
- Qinghao Meng
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
| | - Fan Yu
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
| | - Gan Liu
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
| | - Junyu Zong
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
| | - Qichao Tian
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
| | - Kaili Wang
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
| | - Xiaodong Qiu
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
| | - Can Wang
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
- School of Physics and Electronic Sciences, Changsha University of Science and Technology, Changsha 410114, China
| | - Xiaoxiang Xi
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Yi Zhang
- National Laboratory of Solid State Microstructure, School of Physics, Nanjing University, Nanjing 210093, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
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15
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Tang L, Mao Z, Wang C, Fu Q, Wang C, Zhang Y, Shen J, Yin Y, Shen B, Tan D, Li Q, Wang Y, Medhekar NV, Wu J, Yuan H, Li Y, Fuhrer MS, Zheng C. Giant piezoresistivity in a van der Waals material induced by intralayer atomic motions. Nat Commun 2023; 14:1519. [PMID: 36934098 PMCID: PMC10024745 DOI: 10.1038/s41467-023-37239-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 03/07/2023] [Indexed: 03/20/2023] Open
Abstract
The presence of the van der Waals gap in layered materials creates a wealth of intriguing phenomena different to their counterparts in conventional materials. For example, pressurization can generate a large anisotropic lattice shrinkage along the stacking orientation and/or a significant interlayer sliding, and many of the exotic pressure-dependent properties derive from these mechanisms. Here we report a giant piezoresistivity in pressurized β'-In2Se3. Upon compression, a six-orders-of-magnitude drop of electrical resistivity is obtained below 1.2 GPa in β'-In2Se3 flakes, yielding a giant piezoresistive gauge πp of -5.33 GPa-1. Simultaneously, the sample undergoes a semiconductor-to-semimetal transition without a structural phase transition. Surprisingly, linear dichroism study and theoretical first principles modelling show that these phenomena arise not due to shrinkage or sliding at the van der Waals gap, but rather are dominated by the layer-dependent atomic motions inside the quintuple layer, mainly from the shifting of middle Se atoms to their high-symmetric location. The atomic motions link to both the band structure modulation and the in-plane ferroelectric dipoles. Our work not only provides a prominent piezoresistive material but also points out the importance of intralayer atomic motions beyond van der Waals gap.
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Affiliation(s)
- Lingyun Tang
- School of Physics and Optoelectronics, South China University of Technology, Guangzhou, Guangdong, 510641, China
| | - Zhongquan Mao
- School of Physics and Optoelectronics, South China University of Technology, Guangzhou, Guangdong, 510641, China
| | - Chutian Wang
- Department of Materials Science and Engineering, & ARC Centre of Excellence in Future Low Energy Electronics Technologies, Monash University, Clayton, VIC, Australia
| | - Qi Fu
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, Zhejiang Province, China
| | - Chen Wang
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, Zhejiang Province, China
| | - Yichi Zhang
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, Zhejiang Province, China
| | - Jingyi Shen
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, Zhejiang Province, China
| | - Yuefeng Yin
- Department of Materials Science and Engineering, & ARC Centre of Excellence in Future Low Energy Electronics Technologies, Monash University, Clayton, VIC, Australia
| | - Bin Shen
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou, China
| | - Dayong Tan
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 510640, Guangzhou, Guangdong, China
| | - Qian Li
- Shandong Key Laboratory of Optical Communication Science and Technology, School of Physics Science and Information Technology, Liaocheng University, Liaocheng, 252000, China
| | - Yonggang Wang
- Center for High Pressure Science and Technology Advanced Research (HPSTAR), Beijing, 100094, China
| | - Nikhil V Medhekar
- Department of Materials Science and Engineering, & ARC Centre of Excellence in Future Low Energy Electronics Technologies, Monash University, Clayton, VIC, Australia
| | - Jie Wu
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, Zhejiang Province, China
| | - Huiqiu Yuan
- Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou, China
| | - Yanchun Li
- Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.
| | - Michael S Fuhrer
- ARC Centre of Excellence in Future Low-Energy Electronics Technologies, & School of Physics and Astronomy, Monash University, Melbourne, VIC, 3800, Australia.
| | - Changxi Zheng
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, Zhejiang Province, China.
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16
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Yan S, Xu C, Zhong C, Chen Y, Che X, Luo X, Zhu Y. Phase Instability in van der Waals In 2 Se 3 Determined by Surface Coordination. Angew Chem Int Ed Engl 2023; 62:e202300302. [PMID: 36861653 DOI: 10.1002/anie.202300302] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/16/2023] [Accepted: 03/01/2023] [Indexed: 03/03/2023]
Abstract
van der Waals In2 Se3 has attracted significant attention for its room-temperature 2D ferroelectricity/antiferroelectricity down to monolayer thickness. However, instability and potential degradation pathway in 2D In2 Se3 have not yet been adequately addressed. Using a combination of experimental and theoretical approaches, we here unravel the phase instability in both α- and β'-In2 Se3 originating from the relatively unstable octahedral coordination. Together with the broken bonds at the edge steps, it leads to moisture-facilitated oxidation of In2 Se3 in air to form amorphous In2 Se3-3x O3x layers and Se hemisphere particles. Both O2 and H2 O are required for such surface oxidation, which can be further promoted by light illumination. In addition, the self-passivation effect from the In2 Se3-3x O3x layer can effectively limit such oxidation to only a few nanometer thickness. The achieved insight paves way for better understanding and optimizing 2D In2 Se3 performance for device applications.
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Affiliation(s)
- Shanru Yan
- Department of Applied Physics, Research Institute for Smart Energy, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P.R. China
| | - Chao Xu
- Department of Applied Physics, Research Institute for Smart Energy, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P.R. China
| | - Cenchen Zhong
- Department of Applied Physics, Research Institute for Smart Energy, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P.R. China
| | - Yancong Chen
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, Centre for Physical Mechanics and Biophysics, School of Physics, Sun Yat-sen University, Guangzhou, P.R. China
| | - Xiangli Che
- Department of Applied Physics, Research Institute for Smart Energy, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P.R. China
| | - Xin Luo
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, Centre for Physical Mechanics and Biophysics, School of Physics, Sun Yat-sen University, Guangzhou, P.R. China
| | - Ye Zhu
- Department of Applied Physics, Research Institute for Smart Energy, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, P.R. China
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17
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Chen Z, Sun M, Li H, Huang B, Loh KP. Oscillatory Order-Disorder Transition during Layer-by-Layer Growth of Indium Selenide. NANO LETTERS 2023; 23:1077-1084. [PMID: 36696459 DOI: 10.1021/acs.nanolett.2c04785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
It is important to understand the polymorph transition and crystal-amorphous phase transition in In2Se3 to tap the potential of this material for resistive memory storage. By monitoring layer-by-layer growth of β-In2Se3 during molecular beam epitaxy (MBE), we are able to identify a cyclical order-disorder transition characterized by a periodic alternation between a glassy-like metastable subunit cell film consisting of n < 5 sublayers (nth layers = the number of subunit cell layers), and a highly crystalline β-In2Se3 at n = 5 layers. The glassy phase shows an odd-even alternation between the indium-cluster layer (n = 1, 3) and an In-Se solid solution (n = 2, 4), which suggests the ability of In and Se atoms to diffuse, aggregate, and intermix. These dynamic natures of In and Se atoms contribute to a defect-driven memory resistive behavior in current-voltage sweeps that is different from the ferroelectric switching of α-In2Se3.
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Affiliation(s)
- Zhi Chen
- International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology (ICL-2D MOST), Shenzhen University, Shenzhen518060, People's Republic of China
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, People's Republic of China
| | - Mingzi Sun
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, 999077, People's Republic of China
| | - Haohan Li
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore117543, Singapore
| | - Bolong Huang
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, 999077, People's Republic of China
- Research Centre for Carbon-Strategic Catalysis, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, 999077, People's Republic of China
| | - Kian Ping Loh
- International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology (ICL-2D MOST), Shenzhen University, Shenzhen518060, People's Republic of China
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore117543, Singapore
- Department of Applied Physics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR999077, People's Republic of China
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18
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Giri A, Park G, Jeong U. Layer-Structured Anisotropic Metal Chalcogenides: Recent Advances in Synthesis, Modulation, and Applications. Chem Rev 2023; 123:3329-3442. [PMID: 36719999 PMCID: PMC10103142 DOI: 10.1021/acs.chemrev.2c00455] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The unique electronic and catalytic properties emerging from low symmetry anisotropic (1D and 2D) metal chalcogenides (MCs) have generated tremendous interest for use in next generation electronics, optoelectronics, electrochemical energy storage devices, and chemical sensing devices. Despite many proof-of-concept demonstrations so far, the full potential of anisotropic chalcogenides has yet to be investigated. This article provides a comprehensive overview of the recent progress made in the synthesis, mechanistic understanding, property modulation strategies, and applications of the anisotropic chalcogenides. It begins with an introduction to the basic crystal structures, and then the unique physical and chemical properties of 1D and 2D MCs. Controlled synthetic routes for anisotropic MC crystals are summarized with example advances in the solution-phase synthesis, vapor-phase synthesis, and exfoliation. Several important approaches to modulate dimensions, phases, compositions, defects, and heterostructures of anisotropic MCs are discussed. Recent significant advances in applications are highlighted for electronics, optoelectronic devices, catalysts, batteries, supercapacitors, sensing platforms, and thermoelectric devices. The article ends with prospects for future opportunities and challenges to be addressed in the academic research and practical engineering of anisotropic MCs.
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Affiliation(s)
- Anupam Giri
- Department of Chemistry, Faculty of Science, University of Allahabad, Prayagraj, UP-211002, India
| | - Gyeongbae Park
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Cheongam-Ro 77, Nam-Gu, Pohang, Gyeongbuk790-784, Korea.,Functional Materials and Components R&D Group, Korea Institute of Industrial Technology, Gwahakdanji-ro 137-41, Sacheon-myeon, Gangneung, Gangwon-do25440, Republic of Korea
| | - Unyong Jeong
- Department of Materials Science and Engineering, Pohang University of Science and Technology, Cheongam-Ro 77, Nam-Gu, Pohang, Gyeongbuk790-784, Korea
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19
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Wu Z, Liu K, Mu X, Zhou J. Renormalizing Antiferroelectric Nanostripes in β'-In 2Se 3 via Optomechanics. J Phys Chem Lett 2023; 14:677-684. [PMID: 36637877 DOI: 10.1021/acs.jpclett.2c03226] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Antiferroelectric (AFE) materials have attracted a great deal of attention owing to their high energy conversion efficiency and good tunability. Recently, an exotic two-dimensional AFE material, a β'-In2Se3 monolayer that could host atomically thin AFE nanostripe domains, has been experimentally synthesized and theoretically examined. In this work, we apply first-principles calculations and theoretical estimations to predict that light irradiation can control the nanostripe width of such a system. We suggest that an intermediate near-infrared light (below the bandgap) could effectively harness the thermodynamic Gibbs free energy and thermodynamic stability, and the AFE nanostripe width will gradually decrease. We also propose to use linearly polarized light above the bandgap to generate an AFE nanostripe-specific photocurrent, providing an all-optical pump-probe setup for such AFE nanostripe width phase transitions.
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Affiliation(s)
- Zihang Wu
- Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China
| | - Kun Liu
- Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China
| | - Xingchi Mu
- Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China
| | - Jian Zhou
- Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China
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20
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Han W, Zheng X, Yang K, Tsang CS, Zheng F, Wong LW, Lai KH, Yang T, Wei Q, Li M, Io WF, Guo F, Cai Y, Wang N, Hao J, Lau SP, Lee CS, Ly TH, Yang M, Zhao J. Phase-controllable large-area two-dimensional In 2Se 3 and ferroelectric heterophase junction. NATURE NANOTECHNOLOGY 2023; 18:55-63. [PMID: 36509923 DOI: 10.1038/s41565-022-01257-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 10/06/2022] [Indexed: 06/17/2023]
Abstract
Memory transistors based on two-dimensional (2D) ferroelectric semiconductors are intriguing for next-generation in-memory computing. To date, several 2D ferroelectric materials have been unveiled, among which 2D In2Se3 is the most promising, as all the paraelectric (β), ferroelectric (α) and antiferroelectric (β') phases are found in 2D quintuple layers. However, the large-scale synthesis of 2D In2Se3 films with the desired phase is still absent, and the stability for each phase remains obscure. Here we show the successful growth of centimetre-scale 2D β-In2Se3 film by chemical vapour deposition including distinct centimetre-scale 2D β'-In2Se3 film by an InSe precursor. We also demonstrate that as-grown 2D β'-In2Se3 films on mica substrates can be delaminated or transferred onto flexible or uneven substrates, yielding α-In2Se3 films through a complete phase transition. Thus, a full spectrum of paraelectric, ferroelectric and antiferroelectric 2D films can be readily obtained by means of the correlated polymorphism in 2D In2Se3, enabling 2D memory transistors with high electron mobility, and polarizable β'-α In2Se3 heterophase junctions with improved non-volatile memory performance.
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Affiliation(s)
- Wei Han
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
- Hubei Yangtze Memory Laboratories, Hubei University, Wuhan, China
| | - Xiaodong Zheng
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
| | - Ke Yang
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
- Department of Computing, The Hong Kong Polytechnic University, Kowloon, China
| | - Chi Shing Tsang
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
| | - Fangyuan Zheng
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
| | - Lok Wing Wong
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
| | - Ka Hei Lai
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
| | - Tiefeng Yang
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, China
- City University of Hong Kong, Shenzhen Research Institute, Shenzhen, China
| | - Qi Wei
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
| | - Mingjie Li
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
| | - Weng Fu Io
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
| | - Feng Guo
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
| | - Yuan Cai
- Department of Physics, Hong Kong University of Science and Technology, Hong Kong, China
| | - Ning Wang
- Department of Physics, Hong Kong University of Science and Technology, Hong Kong, China
| | - Jianhua Hao
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
| | - Shu Ping Lau
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China
| | - Chun-Sing Lee
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, China
| | - Thuc Hue Ly
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, China.
- City University of Hong Kong, Shenzhen Research Institute, Shenzhen, China.
| | - Ming Yang
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China.
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China.
| | - Jiong Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, China.
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China.
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21
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Anisotropic electronic transport properties in two-dimensional ferroelectric In 2Se 3 monolayer. Chem Phys 2023. [DOI: 10.1016/j.chemphys.2023.111822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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22
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Zheng X, Han W, Yang K, Wong LW, Tsang CS, Lai KH, Zheng F, Yang T, Lau SP, Ly TH, Yang M, Zhao J. Phase and polarization modulation in two-dimensional In 2Se 3 via in situ transmission electron microscopy. SCIENCE ADVANCES 2022; 8:eabo0773. [PMID: 36269828 PMCID: PMC9586485 DOI: 10.1126/sciadv.abo0773] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 09/02/2022] [Indexed: 06/16/2023]
Abstract
Phase transitions in two-dimensional (2D) materials promise reversible modulation of material physical and chemical properties in a wide range of applications. 2D van der Waals layered In2Se3 with bistable out-of-plane ferroelectric (FE) α phase and antiferroelectric (AFE) β' phase is particularly attractive for its electronic applications. However, reversible phase transition in 2D In2Se3 remains challenging. Here, we introduce two factors, dimension (thickness) and strain, which can effectively modulate the phases of 2D In2Se3. We achieve reversible AFE and out-of-plane FE phase transition in 2D In2Se3 by delicate strain control inside a transmission electron microscope. In addition, the polarizations in 2D FE In2Se3 can also be manipulated in situ at the nanometer-sized contacts, rendering remarkable memristive behavior. Our in situ transmission electron microscopy (TEM) work paves a previously unidentified way for manipulating the correlated FE phases and highlights the great potentials of 2D ferroelectrics for nanoelectromechanical and memory device applications.
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Affiliation(s)
- Xiaodong Zheng
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
| | - Wei Han
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
| | - Ke Yang
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
- Department of Computing, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
| | - Lok Wing Wong
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
| | - Chi Shing Tsang
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
| | - Ka Hei Lai
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
| | - Fangyuan Zheng
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
| | - Tiefeng Yang
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Shu Ping Lau
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
| | - Thuc Hue Ly
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Ming Yang
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
| | - Jiong Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen, China
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23
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Fortes AD, Parker SF. Structure and Spectroscopy of Iron Pentacarbonyl, Fe(CO) 5. J Am Chem Soc 2022; 144:17376-17386. [PMID: 36112983 PMCID: PMC9523711 DOI: 10.1021/jacs.2c01469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
We have re-investigated the structure and vibrational
spectroscopy
of the iconic molecule iron pentacarbonyl, Fe(CO)5, in
the solid state by neutron scattering methods. In addition to the
known C2/c structure, we find that
Fe(CO)5 undergoes a displacive ferroelastic phase transition
at 105 K to a P1̅ structure. We propose that
this is a result of certain intermolecular contacts becoming shorter
than the sum of the van der Waals radii, resulting in an increased
contribution of electrostatic repulsion to these interactions; this
is manifested as a strain that breaks the symmetry of the crystal.
Evaluation of the strain in a triclinic crystal required a description
of the spontaneous strain in terms of a second-rank tensor, something
that is feasible with high-precision powder diffraction data but practically
very difficult using strain gauges on a single crystal of such low
symmetry. The use of neutron vibrational spectroscopy (which is not
subject to selection rules) has allowed the observation of all the
fundamentals below 700 cm–1 for the first time.
This has resulted in the re-assignment of several of the modes. Surprisingly,
density functional theory calculations that were carried out to support
the spectral assignments provided a poor description of the spectra.
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Affiliation(s)
- A. Dominic Fortes
- ISIS Neutron and Muon Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Oxfordshire OX11 0QX, U.K
| | - Stewart F. Parker
- ISIS Neutron and Muon Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Oxfordshire OX11 0QX, U.K
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24
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Huo D, Bai Y, Lin X, Deng J, Pan Z, Zhu C, Liu C, Yu H, Zhang C. Tuning of the Valley Structures in Monolayer In 2Se 3/WSe 2 Heterostructures via Ferroelectricity. NANO LETTERS 2022; 22:7261-7267. [PMID: 35993689 DOI: 10.1021/acs.nanolett.2c02871] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Recent findings of two-dimensional ferroelectric (FE) materials have enabled the integration of nonvolatile FE functions into device applications based on van der Waals (vdW) heterojunctions (HJs), resulting in versatile technological advances. In this paper, we report the results of direct probing of the electronic structures of In2Se3/WSe2 heterostructures at the single-layer limit, where monolayer (ML)-In2Se3 was found to be either antiferroelectric (AFE, β') or ferroelectric (β*) at sufficiently low temperatures. A general type-II band alignment was revealed for this heterostructure. Moreover, we observed significant modulations of the valley structures of WSe2, and in situ transformations between the FE and AFE In2Se3 phases demonstrated the dominant role of the polarizations in the top ML-In2Se3 layer. The observed phenomena can be attributed to the combination of both the linear and quadratic Stark shifts from the out-of-plane electric field, which has only been previously theoretically explored for ML-transition metal dichalcogenides (TMDs).
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Affiliation(s)
- Da Huo
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Yusong Bai
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Xiaoyu Lin
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Jinghao Deng
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Zemin Pan
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Chao Zhu
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Chuansheng Liu
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
| | - Hongyi Yu
- Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing and School of Physics and Astronomy, Sun Yat-Sen University (Zhuhai Campus), Zhuhai 519082, China
- State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-Sen University (Guangzhou Campus), Guangzhou 510275, China
| | - Chendong Zhang
- School of Physics and Technology, Wuhan University, Wuhan 430072, China
- Wuhan Institute of Quantum Technology, Wuhan 430206, China
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25
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Yoshida T, Takaishi S, Guérin L, Kojima T, Ohtsu H, Kawano M, Miyamoto T, Okamoto H, Kato K, Takata M, Hosomi Y, Yoshida S, Shigekawa H, Tanaka H, Kuroda SI, Iguchi H, Breedlove BK, Li ZY, Yamashita M. Hydrogen Bonding Propagated Phase Separation in Quasi-Epitaxial Single Crystals: A Pd-Br Molecular Insulator. Inorg Chem 2022; 61:14067-14074. [PMID: 36006962 DOI: 10.1021/acs.inorgchem.2c02078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In condensed matter, phase separation is strongly related to ferroelasticity, ferroelectricity, ferromagnetism, electron correlation, and crystallography. These ferroics are important for nano-electronic devices such as non-volatile memory. However, the quantitative information regarding the lattice (atomic) structure at the border of phase separation is unclear in many cases. Thus, to design electronic devices at the molecular level, a quantitative electron-lattice relationship must be established. Herein, we elucidated a PdII-PdIV/PdIII-PdIII phase transition and phase separation mechanism for [Pd(cptn)2Br]Br2 (cptn = 1R,2R-diaminocyclopentane), propagated through a hydrogen-bonding network. Although the Pd···Pd distance was used to determine the electronic state, the differences in the Pd···Pd distance and the optical gap between Mott-Hubbard (MH) and charge-density-wave (CDW) states were only 0.012 Å and 0.17 eV, respectively. The N-H···Br···H-N hydrogen-bonding network functioned as a jack, adjusting the structural difference dynamically, and allowing visible ferroelastic phase transition/separation in a fluctuating N2 gas flow. Additionally, the effect of the phase separation on the spin susceptibility and electrical conductivity were clarified to represent the quasi-epitaxial crystals among CDW-MH states. These results indicate that the phase transitions and separations could be controlled via atomic and molecular level modifications, such as the addition of hydrogen bonding.
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Affiliation(s)
- Takefumi Yoshida
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza- Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Shinya Takaishi
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza- Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Laurent Guérin
- Institut de Physique de Rennes, Université de Rennes 1, 263 Av. du Général Leclerc, Rennes Cedex 35042, France
| | - Tatsuhiro Kojima
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Hiroyoshi Ohtsu
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Masaki Kawano
- Department of Chemistry, School of Science, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Tatsuya Miyamoto
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561, Japan
| | - Hiroshi Okamoto
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561, Japan
| | - Kenichi Kato
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Masaki Takata
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Yuka Hosomi
- Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8573, Japan
| | - Shoji Yoshida
- Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8573, Japan
| | - Hidemi Shigekawa
- Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8573, Japan
| | - Hisaaki Tanaka
- Department of Applied Physics, Graduate School of Engineering, Nagoya, University, Furocho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Shin-Ichi Kuroda
- Department of Applied Physics, Graduate School of Engineering, Nagoya, University, Furocho, Chikusa-ku, Nagoya 464-8603, Japan
| | - Hiroaki Iguchi
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza- Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Brian K Breedlove
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza- Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan
| | - Zhao-Yang Li
- School of Materials Science and Engineering, Nankai University, Tianjin 300350, China
| | - Masahiro Yamashita
- Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza- Aoba, Aoba-ku, Sendai, Miyagi 980-8578, Japan.,School of Materials Science and Engineering, Nankai University, Tianjin 300350, China
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26
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Abstract
Pyroelectricity describes the generation of electricity by temporal temperature change in polar materials1-3. When free-standing pyroelectric materials approach the 2D crystalline limit, how pyroelectricity behaves remained largely unknown. Here, using three model pyroelectric materials whose bonding characters along the out-of-plane direction vary from van der Waals (In2Se3), quasi-van der Waals (CsBiNb2O7) to ionic/covalent (ZnO), we experimentally show the dimensionality effect on pyroelectricity and the relation between lattice dynamics and pyroelectricity. We find that, for all three materials, when the thickness of free-standing sheets becomes small, their pyroelectric coefficients increase rapidly. We show that the material with chemical bonds along the out-of-plane direction exhibits the greatest dimensionality effect. Experimental observations evidence the possible influence of changed phonon dynamics in crystals with reduced thickness on their pyroelectricity. Our findings should stimulate fundamental study on pyroelectricity in ultra-thin materials and inspire technological development for potential pyroelectric applications in thermal imaging and energy harvesting.
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27
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Intercalation-driven ferroelectric-to-ferroelastic conversion in a layered hybrid perovskite crystal. Nat Commun 2022; 13:3104. [PMID: 35662239 PMCID: PMC9166815 DOI: 10.1038/s41467-022-30822-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 05/19/2022] [Indexed: 11/09/2022] Open
Abstract
Two-dimensional (2D) organic-inorganic hybrid perovskites have attracted intense interests due to their quantum well structure and tunable excitonic properties. As an alternative to the well-studied divalent metal hybrid perovskite based on Pb2+, Sn2+ and Cu2+, the trivalent metal-based (eg. Sb3+ with ns2 outer-shell electronic configuration) hybrid perovskite with the A3M2X9 formula (A = monovalent cations, M = trivalent metal, X = halide) offer intriguing possibilities for engineering ferroic properties. Here, we synthesized 2D ferroelectric hybrid perovskite (TMA)3Sb2Cl9 with measurable in-plane and out-of-plane polarization. Interestingly, (TMA)3Sb2Cl9 can be intercalated with FeCl4 ions to form a ferroelastic and piezoelectric single crystal, (TMA)4-Fe(iii)Cl4-Sb2Cl9. Density functional theory calculations were carried out to investigate the unusual mechanism of ferroelectric-ferroelastic crossover in these crystals.
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28
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Jeong J, Kim HS, Kwon G, Jeong K, Lee H, Lee JH, Park M, Lee C, Yu S, Kim H, Im S, Yoo K, Lee E, Cho MH. Ferroelastic-Ferroelectric Multiferroicity in van der Waals Rhenium Dichalcogenides. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2108777. [PMID: 35293650 DOI: 10.1002/adma.202108777] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 03/11/2022] [Indexed: 06/14/2023]
Abstract
2D multiferroics with combined ferroic orders have gained attention owing to their novel functionality and underlying science. Intrinsic ferroelastic-ferroelectric multiferroicity in single-crystalline van der Waals rhenium dichalcogenides, whose symmetries are broken by the Peierls distortion and layer-stacking order, is demonstrated. Ferroelastic switching of the domain orientation and accompanying anisotropic properties is achieved with 1% uniaxial strain using the polymer encapsulation method. Based on the electron localization function and bond dissociation energy of the Re-Re bonds, the change in bond configuration during the evolution of the domain wall and the preferred switching between the two specific orientation states are explained. Furthermore, the ferroelastic switching of ferroelectric polarization is confirmed using the photovoltaic effect. The study provides insights into the reversible bond-switching process and potential applications based on 2D multiferroicity.
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Affiliation(s)
- Jaehun Jeong
- Department of Physics, Yonsei University, Seoul, 03722, Republic of Korea
| | - Hyeon-Sik Kim
- Department of Physics, Yonsei University, Seoul, 03722, Republic of Korea
| | - Gihyeon Kwon
- Department of Physics, Yonsei University, Seoul, 03722, Republic of Korea
| | - Kwangsik Jeong
- Division of Physics and Semiconductor Science, Dongguk University, Seoul, 04620, Republic of Korea
| | - Hyangsook Lee
- Samsung Advanced Institute of Technology, Suwon, 16678, Republic of Korea
| | - Ji Hye Lee
- Center for Correlated Electron Systems (CCES), Institute of Basic Science (IBS), Seoul, 08826, Korea
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Korea
| | - Myunguk Park
- Department of Physics, Yonsei University, Seoul, 03722, Republic of Korea
| | - Changjun Lee
- Department of Physics, Yonsei University, Seoul, 03722, Republic of Korea
| | - Sanghyuck Yu
- Department of Physics, Yonsei University, Seoul, 03722, Republic of Korea
| | - Heegoo Kim
- Samsung Advanced Institute of Technology, Suwon, 16678, Republic of Korea
| | - Seongil Im
- Department of Physics, Yonsei University, Seoul, 03722, Republic of Korea
| | - Kyunghwa Yoo
- Department of Physics, Yonsei University, Seoul, 03722, Republic of Korea
| | - Eunha Lee
- Samsung Advanced Institute of Technology, Suwon, 16678, Republic of Korea
| | - Mann-Ho Cho
- Department of Physics, Yonsei University, Seoul, 03722, Republic of Korea
- Department of System Semiconductor Engineering, Yonsei University, Seoul, 03722, Republic of Korea
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29
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Liang Y, Lv X, Frauenheim T. Carrier doping-induced strong magnetoelastic coupling in 2D lattice. NANOSCALE 2022; 14:3261-3268. [PMID: 35166297 DOI: 10.1039/d1nr08459c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The realization of intertwined ferroelasticity and ferromagnetism in two-dimensional (2D) lattices is of great interest for broad nanoscale applications but still remains a remarkable challenge. Here, we propose an alternative approach to realize the strongly coupled ferromagnetism and ferroelasticity by carrier doping. We demonstrate that prototypical 2D β-PbO is dynamically, thermally and mechanically stable. Under hole doping, 2D β-PbO possesses ferromagnetism and ferroelasticity simultaneously. Moreover, the robustness of ferromagnetic and ferroelastic orders is doping tunable. In particular, 2D β-PbO features an in-plane easy magnetization axis that is coupled with the lattice direction, enabling the ferroelastic manipulation of the spin direction. Furthermore, the efficient ferroelastic control of the anisotropic optical property and spin splitting in 2D β-PbO are also clarified. Our study highlights a new direction for 2D magnetoelastic research and enables the possibility for multifunctional devices.
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Affiliation(s)
- Yan Liang
- Bremen Center for Computational Materials Science, University of Bremen, 28359 Bremen, Germany.
| | - Xingshuai Lv
- Shenzhen JL Computational Science and Applied Research Institute, 518109 Shenzhen, P.R. China
| | - Thomas Frauenheim
- Bremen Center for Computational Materials Science, University of Bremen, 28359 Bremen, Germany.
- Shenzhen JL Computational Science and Applied Research Institute, 518109 Shenzhen, P.R. China
- Beijing Computational Science Research Center, 100193 Beijing, P.R. China
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Zhang Z, Nie J, Zhang Z, Yuan Y, Fu YS, Zhang W. Atomic Visualization and Switching of Ferroelectric Order in β-In 2 Se 3 Films at the Single Layer Limit. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2106951. [PMID: 34755394 DOI: 10.1002/adma.202106951] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/24/2021] [Indexed: 06/13/2023]
Abstract
2D ferroelectrics have received wide interest due to the remarkable quantum states of emerging physics at reduced dimensionality, associated with their exotic properties in high-performance and nonvolatile functional devices. Here, by combing molecular beam epitaxy synthesis and scanning tunneling microscopy characterization, two metastable phases of layered In2 Se3 films: β'- and β*-In2 Se3 are reported, which develop different types of in-plane spontaneous polarizations, thus resulting in different striped morphologies. The anti-ferroelectric order in β'-In2 Se3 and ferroelectric order of β*-In2 Se3 are identified, respectively, down to the 2D limit by comprehensive investigations of structural and spectroscopic signatures, including the lattice distortion, the spatial profile of images, the formation of domain structure, and the electronic band-bending by polarization charges at edges. The ferroelectric switching between those two phases are further controlled via applying an electric field generated from the scanning tunneling microscopy tip in a reversible manner. The intriguing tunability between the (anti-)ferroelectric orders in the 2D limit provides a promising platform for studying the interplay between electronic structure and ferroelectricity in van der Waals materials, and promotes potential development of miniaturized transistors and memory devices based on electric polarizations.
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Affiliation(s)
- Zhimo Zhang
- School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Jinhua Nie
- School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Zhihao Zhang
- School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Yuan Yuan
- School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Ying-Shuang Fu
- School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Wenhao Zhang
- School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan, 430074, China
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Wei XK, Dunin-Borkowski RE, Mayer J. Structural Phase Transition and In-Situ Energy Storage Pathway in Nonpolar Materials: A Review. MATERIALS 2021; 14:ma14247854. [PMID: 34947446 PMCID: PMC8707040 DOI: 10.3390/ma14247854] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/09/2021] [Accepted: 12/16/2021] [Indexed: 11/27/2022]
Abstract
Benefitting from exceptional energy storage performance, dielectric-based capacitors are playing increasingly important roles in advanced electronics and high-power electrical systems. Nevertheless, a series of unresolved structural puzzles represent obstacles to further improving the energy storage performance. Compared with ferroelectrics and linear dielectrics, antiferroelectric materials have unique advantages in unlocking these puzzles due to the inherent coupling of structural transitions with the energy storage process. In this review, we summarize the most recent studies about in-situ structural phase transitions in PbZrO3-based and NaNbO3-based systems. In the context of the ultrahigh energy storage density of SrTiO3-based capacitors, we highlight the necessity of extending the concept of antiferroelectric-to-ferroelectric (AFE-to-FE) transition to broader antiferrodistortive-to-ferrodistortive (AFD-to-FD) transition for materials that are simultaneously ferroelastic. Combining discussion of the factors driving ferroelectricity, electric-field-driven metal-to-insulator transition in a (La1−xSrx)MnO3 electrode is emphasized to determine the role of ionic migration in improving the storage performance. We believe that this review, aiming at depicting a clearer structure–property relationship, will be of benefit for researchers who wish to carry out cutting-edge structure and energy storage exploration.
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Affiliation(s)
- Xian-Kui Wei
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Research Centre Jülich, 52425 Jülich, Germany; (R.E.D.-B.); (J.M.)
- Correspondence:
| | - Rafal E. Dunin-Borkowski
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Research Centre Jülich, 52425 Jülich, Germany; (R.E.D.-B.); (J.M.)
| | - Joachim Mayer
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons, Research Centre Jülich, 52425 Jülich, Germany; (R.E.D.-B.); (J.M.)
- Gemeinschaftslabor für Elektronenmikroskopie (GFE), RWTH Aachen University, 52074 Aachen, Germany
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