Article
Chemistry, Multidisciplinary
Qiucheng Li, Xiaolong Liu, Eden B. Aklile, Shaowei Li, Mark C. Hersam
Summary: The study reports the self-assembly of mixed-dimensional lateral heterostructures consisting of 2D metallic borophene and 1D semiconducting armchair-oriented graphene nanoribbons (aGNRs). The systematic study and refinement of on-surface polymerization process from monomers to organometallic intermediates to demetallization result in borophene/aGNR lateral heterojunctions with structurally and electronically abrupt interfaces, providing insight for precise nanoelectronics.
Article
Chemistry, Multidisciplinary
Meng-Kai Lin, Guan-Hao Chen, Ciao-Lin Ho, Wei-Chen Chueh, Joseph Andrew Hlevyack, Chia-Nung Kuo, Tsu-Yi Fu, Juhn-Jong Lin, Chin Shan Lue, Wen-Hao Chang, Noriaki Takagi, Ryuichi Arafune, Tai-Chang Chiang, Chun-Liang Lin
Summary: Monolayer transition metal dichalcogenides show tunability in electronic properties, with bandgap modulation possible through control of tunneling current. Monolayer PtTe2 exhibits a reversible semiconductor-to-metal transition at moderate tunneling current, attributed to its surface electronic structure coupling with the tunneling tip.
Article
Chemistry, Multidisciplinary
Quanzhen Zhang, Yanhui Hou, Teng Zhang, Ziqiang Xu, Zeping Huang, Peiwen Yuan, Liangguang Jia, Huixia Yang, Yuan Huang, Wei Ji, Jingsi Qiao, Xu Wu, Yeliang Wang
Summary: The researchers used scanning tunneling microscopy and spectroscopy to study the evolution of electronic structures at the interface of a phase-engineered monolayer NbSe2 heterostructure. They observed the penetration of the metallic state H-NbSe2 into the Mott insulating state T-NbSe2, with a prominent CDW proximity effect, and detected an insulating Mott gap collapse at the electronic phase transition region. Theoretical calculations suggested that this collapse could be attributed to electron doping induced by the interface, providing insights into controlling Mott insulating states through phase engineering.
Article
Materials Science, Multidisciplinary
Daniela Dombrowski, Abdus Samad, Kai Mehlich, Thais Chagas, Udo Schwingenschlogl, Carsten Busse
Summary: We prepare monolayers of tantalum sulfide on Au(111) through evaporating tantalum in the presence of H2S. Depending on the sulfur concentration, either 2H-TaS2 monolayers or TaS monolayers are formed. Using scanning tunneling microscopy and density functional theory calculations, we investigate the alignment of the layers with the substrate and the formation of heterostructures. We observe mirror twin boundaries within 2H-TaS2 along the S- and Ta-edge.
Article
Physics, Multidisciplinary
Gefei Niu, Jianchen Lu, Jianqun Geng, Shicheng Li, Hui Zhang, Wei Xiong, Zilin Ruan, Yong Zhang, Boyu Fu, Lei Gao, Jinming Cai
Summary: This study systematically investigates the electronic properties of strained CuSe monolayer on Cu(111) substrate and discovers the modulation effect on electronic properties caused by strain. The findings not only enrich the fundamental understanding of the influence of strain on electronic properties at the 2D limit, but also provide a benchmark for the development of 2D semiconductor materials.
FRONTIERS OF PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Wataru Nishiyama, Tomonori Nishimura, Keiji Ueno, Takashi Taniguchi, Kenji Watanabe, Kosuke Nagashio
Summary: Detailed electrical transport measurements were conducted on PdSe2 to reveal a bandgap energy of approximately 0.3 eV, confirming its status as a middle gap semiconductor and demonstrating the contribution of the depletion layer to its transfer characteristics.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Kaihui Li, Feiping Xiao, Wen Guan, Yulong Xiao, Chang Xu, Jinding Zhang, Chenfang Lin, Dong Li, Qingjun Tong, Si-Yu Li, Anlian Pan
Summary: Moire superlattices exhibit a magnification effect and are sensitive to both external disturbances and internal atomic reconstructions. Long-wavelength WS2 superlattices can be reconstructed into various moire morphologies, ranging from regular hexagons to heavily deformed shapes. The interaction between external nonuniform heterostrain and intrinsic atomic reconstruction is responsible for this interesting evolution of moire structures.
Article
Chemistry, Multidisciplinary
Scott Stonemeyer, Mehmet Dogan, Jeffrey D. Cain, Amin Azizi, Derek C. Popple, Austin Culp, Chengyu Song, Peter Ercius, Marvin L. Cohen, Alex Zettl
Summary: Fine control over material synthesis on the nanoscale has allowed for the selective creation of one-dimensional TaTe3 chains or two-dimensional TaTe2 nanoribbons using carbon nanotube reaction vessels. This control extends to the number of chains or the thickness and width of nanoribbons. Transmission electron microscopy and scanning transmission electron microscopy provide detailed atomic structure of the encapsulated materials, revealing complex superstructures such as multichain spiraling and multilayer moire patterns.
Article
Physics, Multidisciplinary
Yumu Yang, Qilong Wu, Jiaqi Deng, Jing Wang, Yu Xia, Xiaoshuai Fu, Qiwei Tian, Li Zhang, Long-Jing Yin, Yuan Tian, Sheng-Yi Xie, Lijie Zhang, Zhihui Qin
Summary: A new method to synthesize semiconducting Cu2Se by direct selenization of Cu(111) has been developed in this study, with detailed structural and electronic properties determined through a combination of experimental measurements and first-principles calculations. The observed moire pattern suggests a lattice mismatch between Cu2Se and the underlying Cu(111)-root 3 x root 3 surface. The synthesized Cu2Se exhibits a band gap of approximately 0.78 eV, consistent with both experimental and computational results.
Article
Chemistry, Multidisciplinary
Qilong Wu, Xiaoshuai Fu, Ke Yang, Hongyu Wu, Li Liu, Li Zhang, Yuan Tian, Long-Jing Yin, Wei-Qing Huang, Wen Zhang, Ping Kwan Johnny Wong, Lijie Zhang, Andrew T. S. Wee, Zhihui Qin
Summary: This study demonstrates a practical approach to producing highly crystalline monolayer MoSe2 using high-temperature-annealed Au foil as a weakly interacting substrate for atmospheric pressure chemical vapor deposition. The low-temperature scanning tunneling microscopy/spectroscopy measurements reveal a honeycomb structure of MoSe2 with a quasi-particle bandgap of 1.96 eV. The weak coupling between the Au(100) surface and MoSe2 is critical for easy transfer of monolayers to another host substrate.
Letter
Chemistry, Multidisciplinary
Mo-Han Zhang, Ya-Ning Ren, Qi Zheng, Xiao-Feng Zhou, Lin He
Summary: Two-dimensional h-BN and TMDs are commonly used as substrates for graphene due to their insulating and atomically flat properties. However, this study reveals unexpected sensitivity of graphene's electronic properties to these insulating substrates, even when the moire pattern generated between them is small. The electronic density in graphene exhibits a robust and long-ranged superperiodicity in graphene/TMD heterostructures, which arises from electron scattering between the two valleys of graphene. Scanning tunneling microscope and spectroscopy techniques reveal three distinct atomic-scale patterns of electronic density in every graphene/TMD heterostructure.
Article
Chemistry, Multidisciplinary
Shuangyuan Pan, Min Hong, Lijie Zhu, Wenzhi Quan, Zehui Zhang, Yahuan Huan, Pengfei Yang, Fangfang Cui, Fan Zhou, Jingyi Hu, Feipeng Zheng, Yanfeng Zhang
Summary: This study reports the direct synthesis of mono- to few-layer Ni-tellurides, including 1T-NiTe2 and Ni-rich stoichiometric phases, on graphene/SiC substrates under ultra-high-vacuum conditions. Through atomic-scale scanning tunneling microscopy observations and density functional theory calculations, the researchers obtained detailed information about the phase modulation of Ni-tellurides and self-intercalated compounds. Additionally, the study also predicts the emergence of superconductivity in bilayer NiTe2 intercalated with 50% Ni.
Article
Chemistry, Physical
Nan Si, Tao Shen, Xinyi Liu, Dechun Zhou, Qingmin Ji, Wei Liu, Shuang Li, Tianchao Niu
Summary: In this study, lateral 2D heterostructures were constructed using blue phosphorene and tetrafluoro-tetracyanoquinodimethane as building blocks. Gold adatoms were used to link the semiconducting F(4)TCNQ-Au metal organic framework and the metallic blue phosphorene-Au network, resulting in a structurally and electrically abrupt interface. This approach offers flexibility and control that can be extended to other metal-organic species and 2D materials for the development of atomically thin in-plane superlattice and devices.
Article
Chemistry, Multidisciplinary
Daniel J. Rizzo, Sara Shabani, Bjarke S. Jessen, Jin Zhang, Alexander S. McLeod, Carmen Rubio-Verdu, Francesco L. Ruta, Matthew Cothrine, Jiaqiang Yan, David G. Mandrus, Stephen E. Nagler, Angel Rubio, James C. Hone, Cory R. Dean, Abhay N. Pasupathy, D. N. Basov
Summary: The researchers successfully created nanometer-scale lateral p-n junctions using graphene/alpha-RuCl3 heterostructure near graphene nanobubbles. Through STM/STS and s-SNOM techniques, they investigated the electronic and optical responses of nanobubble p-n junctions, achieving p-n junctions with a width of around 3 nm and an electric field of approximately 10(8) V/m. The study also utilized ab initio density functional theory calculations to corroborate experimental data and provide insights into charge transfer mechanisms in 2D materials.
Article
Chemistry, Multidisciplinary
Yong Zhang, Jianchen Lu, Yang Li, Baijin Li, Zilin Ruan, Hui Zhang, Zhenliang Hao, Shijie Sun, Wei Xiong, Lei Gao, Long Chen, Jinming Cai
Summary: Doping graphene nanoribbons (GNRs) with heteroatoms is an effective method to adjust the electronic structures of GNRs for future device applications. In this study, nitrogen-doped armchair GNRs with N=9 were successfully synthesized on the Au(111) surface, and it was found that the different covalent bonds formed in the GNR backbone affect the band structure and band gap of the GNRs.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Letter
Materials Science, Multidisciplinary
Xue-Yan Wang, Hui Guo, Jin-An Shi, Yi Biao, Yan Li, Guang-Yuan Han, Shuai Zhang, Kai Qian, Wu Zhou, Xiao Lin, Shi-Xuan Du, Cheng-Min Shen, Hong-Liang Lu, Hong-Jun Gao
Article
Physics, Multidisciplinary
Li Geng, Guo Hui, Gao Hong-Jun
Summary: Compared with three-dimensional materials, two-dimensional materials exhibit superior properties in terms of electronics, optics, thermics, and mechanics due to their reduced dimensionality. Fabricating materials under ultra-high vacuum has advantages and is widely adopted in the growth of 2D materials.
ACTA PHYSICA SINICA
(2022)
Article
Physics, Multidisciplinary
Qi Zheng, Li Huang, Deliang Bao, Rongting Wu, Yan Li, Xiao Lin, Shixuan Du, Hong-Jun Gao
Summary: The linkage structures between monomers have significant impacts on the properties of polymers. In this study, the dihydropentalene linkage structure in poly-naphthalocyanine on Ag(110) surface was successfully constructed, and a possible formation path with reconstruction steps was proposed. The controlled experiment on Ag(100) surface showed that the grooved substrate is necessary for the formation of dihydropentalene structures. This work provides insights into the surface restricted reactions that can yield special structures in organic polymers.
Article
Chemistry, Physical
Zhipeng Song, Juxia Yi, Jing Qi, Qi Zheng, Zhili Zhu, Lei Tao, Yun Cao, Yan Li, Zhaoyan Gao, Ruizi Zhang, Li Huang, Geng Li, Ziqiang Xu, Xu Wu, Yeliang Wang, Chengmin Shen, Yu-Yang Zhang, Hongliang Lu, Xiao Lin, Shixuan Du, Hong-Jun Gao
Summary: This study reports the formation of line defects in monolayer titanium selenide (TiSe2) and their application in catalysis. The research demonstrates that TiSe2 with line defects exhibits good catalytic activity, especially for the hydrogen evolution reaction (HER). Moreover, defects decorated with single Pt atoms show enhanced catalytic activity.
Article
Physics, Multidisciplinary
Zhipeng Song, Jierui Huang, Shuai Zhang, Yun Cao, Chen Liu, Ruizi Zhang, Qi Zheng, Lu Cao, Li Huang, Jiaou Wang, Tian Qian, Hong Ding, Wu Zhou, Yu-Yang Zhang, Hongliang Lu, Chengmin Shen, Xiao Lin, Shixuan Du, Hong-Jun Gao
Summary: An incommensurate superstructure associated with an incommensurate charge density wave (I-CDW) is reported in monolayer TiSe2/CuSe/Cu(111) heterostructure, exhibiting a higher transition temperature than the commensurate CDW in pristine TiSe2.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Yang Song, Kai Qian, Lei Tao, Zhenyu Wang, Hui Guo, Hui Chen, Shuai Zhang, Yu-Yang Zhang, Xiao Lin, Sokrates T. Pantelides, Shixuan Du, Hong-Jun Gao
Summary: This study reports the successful synthesis of an intrinsically honeycomb-patterned form of hydrogenated graphene on Ru(0001) using epitaxial growth followed by hydrogenation. Combining scanning tunneling microscopy observations with density-functional-theory (DFT) calculations, it was revealed that an atomic-hydrogen layer intercalates between graphene and Ru(0001), resulting in a hydrogen honeycomb structure that serves as a template for the final hydrogenation, yielding honeycomb-patterned hydrogenated graphene (HPHG). This growth mechanism provides a new pathway for the fabrication of intrinsically patterned graphene-based materials.
Article
Chemistry, Multidisciplinary
Cheng-Kun Lyu, Yi-Fan Gao, Zi-Ang Gao, Song-Yu Mo, Mu-Qing Hua, En Li, Shu-Qing Fu, Jia-Yan Chen, Pei-Nian Liu, Li Huang, Nian Lin
Summary: In this study, single-layer two-dimensional cMOFs were successfully synthesized using on-surface synthesis method, consisting of HAT molecules and metal atoms. The magnetic moments of different metal atoms were found to vary, which may be attributed to the conjugated core and coordination properties of HAT.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Physics, Multidisciplinary
Geng Li, Shiyu Zhu, Peng Fan, Lu Cao, Hong-Jun Gao
Summary: Researchers have discovered Majorana zero modes (MZMs) in iron-based superconductors, which overcomes the difficulty of constructing complex hybrid artificial structures to observe pure MZMs. MZMs have been observed in various iron-based superconductors, and researchers have conducted studies and observations using scanning tunneling microscopy and other techniques.
Article
Multidisciplinary Sciences
Geng LjD, Haitao YangLE, Peijie Jiang, Cong Wang, Qiuzhen Cheng, Shangjie Tian, Guangyuan Han, Chengmin Shen, Xiao Lin, Hechang Lei, Wei Ji, Ziqiang Wang, Hong-Jun Gao
Summary: This study reports the discovery of a novel unidirectional charge density wave (CDW) order on the surface of chiral crystal CoSi, which is a unique Weyl semimetal with unconventional chiral fermions. The CDW is incommensurate with lattice momentum and crystalline symmetry directions, and exhibits a pi phase shift in the layer stacking direction. The tunneling spectrum shows an energy gap that modulates spatially with the CDW wave vector.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Yadong Gu, Menghu Zhou, Mengdi Zhang, Yanwei Wu, Binbin Ruan, Xingyuan Hou, Fan Zhang, Peijie Jiang, Qingsong Yang, Geng Li, Mingwei Ma, Genfu Chen, Lei Shan, Zhian Ren
Summary: In this study, a one-step synthesis method was reported to grow high-quality Fe(Te,Se) single crystals through minor Mn doping. The as-grown centimeter-sized crystals showed bulk superconductivity with sharp electrical resistivity and magnetic susceptibility transitions, and large specific heat jumps. Moreover, the optimally doped sample exhibited significantly enhanced upper critical field and large self-field critical current density.
SCIENCE CHINA-MATERIALS
(2022)
Article
Multidisciplinary Sciences
Meng Li, Geng Li, Lu Cao, Xingtai Zhou, Xiancheng Wang, Changqing Jin, Ching-Kai Chiu, Stephen J. Pennycook, Ziqiang Wang, Hong-Jun Gao
Summary: By using scanning tunneling microscopy/spectroscopy, an ordered and tunable Majorana zero mode (MZM) lattice has been discovered in naturally strained LiFeAs superconductor. This finding provides a new pathway for future topological quantum computation.
Article
Chemistry, Multidisciplinary
Peng Fan, Hui Chen, Xingtai Zhou, Lu Cao, Geng Li, Meng Li, Guojian Qian, Yuqing Xing, Chengmin Shen, Xiancheng Wang, Changqing Jin, Genda Gu, Hong Ding, Hong-Jun Gao
Summary: We demonstrate the manipulation of Abrikosov vortices on the surfaces of Fe(Te,Se) and LiFeAs by utilizing one-dimensional wrinkles and low-temperature scanning tunneling microscopy/spectroscopy (STM/S). The wrinkles trap the Abrikosov vortices induced by the external magnetic field, and we are able to tailor and manipulate the wrinkles using an STM tip. Surprisingly, we show that the pinned vortices move together with these wrinkles even at high magnetic field up to 6 T. This work provides a universal and effective method for manipulating wrinkle-pinned vortices and simultaneously measuring the local density of states on the surfaces of iron-based superconductors.
Article
Chemistry, Multidisciplinary
Xiao-Bo Wang, Bowen Xia, Cheng-Kun Lyu, Dongwook Kim, En Li, Shu-Qing Fu, Jia-Yan Chen, Pei-Nian Liu, Feng Liu, Nian Lin
Summary: The experimental realization of p-orbital honeycomb-Kagome lattice in a two dimensional metal-organic framework on a Au(111) substrate is achieved by combining two sublattices composed of molecules with p-orbital characteristics. It is demonstrated that p-orbital lattice can be realized in metal-organic frameworks by using molecules with molecular orbitals of p-orbital like symmetry.
COMMUNICATIONS CHEMISTRY
(2023)
Article
Materials Science, Multidisciplinary
Gu Zhang, Chuang Li, Geng Li, Xin Liu, Can-Li Song, Fu-Chun Zhang, Dong E. Liu
Summary: It is predicted that a vortex in a topological superconductor contains a Majorana zero mode (MZM). However, confirming the Majorana signature is easily disrupted by various interruptions. To overcome these interruptions, a novel Majorana hunting protocol is proposed, which relies on dissipation introduced by disorders at the sample-substrate interface. This protocol highlights three features that provide strong evidence for identifying MZM.
