Review
Nanoscience & Nanotechnology
Chunyu Ma, Jianqiao Li, Siqi Zhang, Wubiao Duan, Qingdao Zeng
Summary: Macrocyclic self-assemblies have sparked great interest due to their diverse structures and potential applications in catalysis, magnetism, photovoltaic devices, and organic light-emitting diodes. These assemblies exhibit regular patterns at the liquid/solid interface thanks to their pi-conjugated structures. Recent studies have focused on different shapes of macrocyclic self-assembly structures, all conducted with the assistance of a scanning tunneling microscope at the liquid/solid interface.
Article
Multidisciplinary Sciences
Lucas Schneider, Philip Beck, Levente Rozsa, Thore Posske, Jens Wiebe, Roland Wiesendanger
Summary: Spin chains proximitized by s-wave superconductors are predicted to enter a mini-gapped phase with topologically protected Majorana modes (MMs) localized at their ends. However, the presence of non-topological end states mimicking MM properties can hinder their unambiguous observation. Here, we report on a direct method to exclude the non-local nature of end states via scanning tunneling spectroscopy by introducing a locally perturbing defect on one of the chain's ends. We apply this method to particular end states observed in antiferromagnetic spin chains within a large minigap, thereby proving their topologically trivial character. A minimal model shows that, while wide trivial minigaps hosting end states are easily achieved in antiferromagnetic spin chains, unrealistically large spin-orbit coupling is required to drive the system into a topologically gapped phase with MMs. The methodology of perturbing candidate topological edge modes in future experiments is a powerful tool to probe their stability against local disorder. Spin chains on superconductors have been studied as a possible venue for zero-energy Majorana bound states at the ends of the chain. Here, the authors observe localized end states in antiferromagnetic chains, but rule out a Majorana origin of these states by perturbing them with local defects.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Songsong Li, Hao Yu, Jialing Li, Nicholas Angello, Edward R. Jira, Bo Li, Martin D. Burke, Jeffrey S. Moore, Charles M. Schroeder
Summary: This study demonstrates that molecular junctions undergo a reversible transition from nonresonant tunneling to resonant transport as a function of applied bias, which is related to the molecular frontier orbital energies and electrode Fermi levels. Through transient bias-switching experiments, the reversible nature of this transition is revealed.
Article
Chemistry, Physical
Qingfeng Zhuang, Lijun Zuo, Xiangyang Li, Lyuzhou Ye, Xiao Zheng, Yijing Yan
Summary: In this study, we simulated the tip control process of the Cu-tip/Cc/Fe/Cu(100) junction using density functional theory and hierarchical equations of motion methods. We successfully reproduced the experimental results and revealed the influences of the Fe adatom on the spin-polarization of the substrate and on the Kondo resonance splitting in the dI/dV spectra.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Haojie Guo, Ane Garro-Hernandorena, Antonio J. Martinez-Galera, Jose M. Gomez-Rodriguez
Summary: The growth of lateral heterostructures of graphene and h-BN on Rh(110) surfaces is reported, enabling control over the rotational order of the domains. Perfect lateral matching is observed at the boundaries, and intervalley scattering processes in graphene regions can be observed. These high-quality heterostructures with tunable properties can be used as test beds for developing novel nanomaterials.
Article
Chemistry, Physical
Ting Meng, Xuan Peng, Xunwen Xiao, Ke Deng, Yu-Wu Zhong, Qingdao Zeng
Summary: The mechanism and law of intermolecular interaction between organic photoelectric molecules were investigated in this study using scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. The experimental results showed the influence of triazine derivatives and temperature on the assembly behavior of H4ETTC, and the theoretical calculations provided insights into the underlying mechanisms.
Article
Instruments & Instrumentation
Jonas Heggemann, Linda Lafloer, Philipp Rahe
Summary: The text describes a double sample holder supporting both a metal sample and an insulator crystal for high-resolution scanning probe microscopy experiments, allowing efficient and reliable high-resolution studies of adjacent insulator surfaces.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
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
Physics, Multidisciplinary
Jia-Jun Ma, Kang Wu, Zhen-Yu Wang, Rui-Song Ma, Li-Hong Bao, Qing Dai, Jin-Dong Ren, Hong-Jun Gao
Summary: A novel two-step ambient pressure chemical vapor deposition (CVD) pathway has been reported to grow high-quality MoS2 monolayer on the SiO2 substrate with large crystal size. Electronic information inferred from the four-probe scanning tunneling microscope (4P-STM) image explains the threshold voltage variations observed, while direct van der Pauw transport also confirms its relatively high carrier mobility.
Article
Physics, Multidisciplinary
Yan-Ling Xiong, Jia-Qi Guan, Rui-Feng Wang, Can-Li Song, Xu-Cun Ma, Qi-Kun Xue
Summary: By studying the electronic structure of a modulation-doped Mott insulator, it is found that a universal pseudogap appears in underdoped regions, which is minimally affected by the applied magnetic field and the presence of Sn vacancies. The pseudogap is smeared out at elevated temperatures and changes in size with the spatial confinement of the Mott insulating phase. These findings are highly reminiscent of the electronic phase diagram in doped copper oxide compounds.
Article
Materials Science, Multidisciplinary
W. Dednam, S. Tewari, E. B. Lombardi, J. J. Palacios, J. M. van Ruitenbeek, C. Sabater
Summary: This article studies the dynamic bonding of gold atoms on surfaces under low coordination conditions using low-temperature scanning tunneling microscopy. By conducting experiments with an atomically sharp gold tip and utilizing classical molecular dynamics simulations and density-functional theory calculations, the differences in bonding behavior between different positions are elucidated, as well as providing information on the crystalline classification of the STM tips based on their performance.
Article
Nanoscience & Nanotechnology
Songbin Cui, Tae-Hwan Kim, Ungdon Ham
Summary: Research has found that asymmetric nano-tip shapes can result in different STL spectra in different directions, providing an effective way to characterize the optical properties of nanomaterials by tuning the STL spectra.
ACS APPLIED NANO MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Shijie Sun, Baijin Li, Boyu Fu, Zilin Ruan, Hui Zhang, Wei Xiong, Yong Zhang, Gefei Niu, Jianchen Lu, Xiaoqing Zuo, Lei Gao, Jinming Cai
Summary: Nanoscale low-dimensional chiral architectures have attracted increasing scientific interest due to their potential applications in chiral recognition, separation, and transformation. In this study, large-area two-dimensional chiral networks on Au(111) and one-dimensional metal-liganded chiral chains on Cu(111) were successfully constructed and characterized. The chiral transformation of the chiral networks on Au(111) was analyzed, and the electronic state information was studied using scanning tunneling spectroscopy. The combination of scanning tunneling microscopy and non-contact atomic force microscopy techniques enabled ultra-high-resolution characterization of chiral structures on low-dimensional surfaces.
CHINESE CHEMICAL LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Ying Tan, Jialing Li, Songsong Li, Hao Yang, Teng Chi, Stephen B. B. Shiring, Kangying Liu, Brett M. M. Savoie, Bryan W. W. Boudouris, Charles M. M. Schroeder
Summary: Incorporating temperature- and air-stable organic radical species into molecular designs offers an advantageous means of controlling the properties of electronic materials. However, a complete understanding of the structure-property relationships of organic radical species at the molecular level is still lacking. This study investigates the charge transport properties of nonconjugated molecules containing (2,2,6,6-tetramethyl-piperidin-1-yl)oxyl (TEMPO) radicals using single-molecule charge transport experiments and molecular modeling. The results demonstrate that TEMPO pendant groups promote temperature-independent molecular charge transport and interact with the gold metal electrodes to facilitate high-conductance conformation.
Article
Chemistry, Physical
Shuo Deng, Ran Xu, Weibin Seh, Jiayi Sun, Weifan Cai, Jianping Zou, Qing Zhang
Summary: This paper presents the discovery of direct current (DC) generation through sliding a metal tip against a doped semiconductor. It is found that the DC current generation is degraded with repeated sliding. The study shows that an ultrathin silicon oxide layer can be induced during sliding, and annealing the clean silicon substrate can mitigate current degradation.
Article
Chemistry, Multidisciplinary
Roger Guzman, Shoucong Ning, Ruizi Zhang, Hongtao Liu, Yinhang Ma, Yu-Yang Zhang, Lihong Bao, Haitao Yang, Shiduan Du, Michel Bosman, Stephen J. Pennycook, Hong-Jun Gao, Wu Zhou
Summary: In this study, the local atomic structure and magnetic behavior of V-rich V1+xTe2 nanoplates with embedded V3Te4 nanoclusters have been investigated. The self-intercalated V3Te4 magnetic phase, which possesses a distorted 1T'-like monoclinic structure, is locally stabilized by V intercalations. The phase transition is controlled by the electron doping from the intercalant V ions. The results provide insights into the studies of dilute magnetism at the 2D limit and strategies for the manipulation of magnetism for spintronic applications.
Article
Chemistry, Multidisciplinary
Junjie Wang, Tianping Ying, Jun Deng, Cuiying Pei, Tongxu Yu, Xu Chen, Yimin Wan, Mingzhang Yang, Weiyi Dai, Dongliang Yang, Yanchun Li, Shiyan Li, Soshi Iimura, Shixuan Du, Hideo Hosono, Yanpeng Qi, Jian-gang Guo
Summary: Searching for functional square lattices in layered superconductor systems provides a clue to modify electron behavior and find exotic properties. Structural transformation of trigonal SnAs3 to square SnAs4 under pressure enables the realization of a functional As square lattice in Li0.6Sn2As2 and NaSnAs, resulting in record-high Tc values. The transfer of the conductive channel from out-of-plane to in-plane orbitals facilitates electron hopping within the 2D lattice and enhances superconductivity. Reorienting p-orbitals through a local structure transformation offers an effective strategy for modifying layered superconducting systems.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Physics, Multidisciplinary
Qin Wang, Jie Zhang, Jierui Huang, Jinan Shi, Shuai Zhang, Hui Guo, Li Huang, Hong Ding, Wu Zhou, Yan-Fang Zhang, Xiao Lin, Shixuan Du, Hong-Jun Gao
Summary: Researchers successfully synthesized a monolayer of gold telluride (AuTe) with a honeycomb structure, which suggests that it could be a good candidate for studying two-dimensional Dirac nodal line fermions.
Article
Materials Science, Multidisciplinary
Caimu Wang, Jidong Zhang, Ruibin Liu, Wei Guo
Summary: In this study, molecular dynamics simulations were conducted using the self-consistent charge density functional tight binding method to investigate the thermal decomposition mechanism of condensed phase NTO. It was found that the initial decomposition reaction mainly involved the rupture of intramolecular chemical bonds, and three primary reaction channels were proposed. Surface and molecular vacancy effects were also considered, and it was observed that the activation barriers for nitro group cleavage and H atom migration were lower in these conditions compared to ideal bulk NTO. The proposed reaction mechanism and the effects of surface and molecular vacancy were verified through electronic structure calculations and TG-DSC experiments. This research contributes to the design of HEDMs with improved performance, safety, and usability.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Jiaqiang Sun, Lei Tao, Chenliang Ye, Yu Wang, Ge Meng, Hengyuan Lei, Shenke Zheng, Chuang Xing, Xin Tao, Pengfei Wu, Jiangang Chen, Shixuan Du, Dingsheng Wang, Yadong Li
Summary: A dual-atomic-site catalyst, Ru1Zr1/Co, was designed for Fischer-Tropsch synthesis (FTS), showing enhanced FTS activity and C5+ selectivity. The synergic effect between Ru and Zr single-atom site on Co NPs contributes to the improved performance.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Jun Deng, Jinbo Pan, Yan-Fang Zhang, Shixuan Du
Summary: Databases for charge-neutral 2D building blocks have been established, but a database for charged 2D building blocks is still missing. In this study, a topological-scaling algorithm is used to identify 1028 charged 2D building blocks from the Materials Project database. These building blocks exhibit versatile functionalities and can be assembled to form 353 stable layered materials with enhanced and emergent properties compared to their parent materials. This database expands the design space of functional materials and has implications for fundamental research and potential applications.
Article
Chemistry, Physical
Xiao Chang, Li Huang, Yixuan Gao, Yubin Fu, Ji Ma, Huan Yang, Junzhi Liu, Xiaoshuai Fu, Xiao Lin, Xinliang Feng, Shixuan Du, Hong-Jun Gao
Summary: Successful synthesis of ZGNR with a width of eight carbon zigzag lines and NBN motifs decorated along the edges has been reported. Chemical-bond-resolved nc-AFM imaging confirms the zigzag-terminated edges and the presence of NBN dopants. Intercalation of a silicon layer reveals the electronic states distributed along the zigzag edges. This work enriches the ZGNR family with a new dopant and larger width, providing more candidates for future carbon-based nanoelectronic and spintronic applications.
Article
Chemistry, Physical
Mingquan Xu, De-Liang Bao, Aowen Li, Meng Gao, Dongqian Meng, Ang Li, Shixuan Du, Gang Su, Stephen J. Pennycook, Sokrates T. Pantelides, Wu Zhou
Summary: By improving the stability and sensitivity of the instrument, we have successfully observed the specific vibrational signals between substitutional impurities and neighboring carbon atoms in monolayer graphene. This work allows for the direct observation of local phonon modes with chemical-bonding sensitivity, providing more insights into defect-induced physics in graphene.
Article
Chemistry, Inorganic & Nuclear
Weimin Dong, Yingjie Sun, Henghao Feng, Dazheng Deng, Jun Jiang, Jin Yang, Wei Guo, Libin Tang, Jincheng Kong, Jun Zhao
Summary: A new polyphosphate with complex chain structure and diverse metal cationic coordination environment has been synthesized. This compound exhibits a deep-UV cutoff edge and significantly enlarged birefringence, reaching a new height among reported mixed alkali metal and alkaline earth metal phosphate. The enlarged birefringence mainly originates from the arrangement of chains in an inverted zigzag.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Jidong Zhang, Wei Guo, Yugui Yao
Summary: In this study, a deep neural network potential model called NNP_Shock was used to simulate shock-induced detonation of energetic materials. The model provides DFT accuracy but with significantly increased computational efficiency, which allows for the study of detonation performance and shock sensitivity of those materials.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Physics, Multidisciplinary
Bingyao Liu, Yu -Tian Zhang, Ruixi Qiao, Ruochen Shi, Yuehui Li, Quanlin Guo, Jiade Li, Xiaomei Li, Li Wang, Jiajie Qi, Shixuan Du, Xinguo Ren, Kaihui Liu, Peng Gao, Yu -Yang Zhang
Summary: We investigated the twist-angle-dependent coupling effects of h-BN/graphene heterostructures and found that moire potentials alter the band structure of graphene, resulting in a redshift of the intralayer transition at the M point. We also observed tunable vertical transition energies in the range of 5.1-5.6 eV due to the twisting of the Brillouin zone of h-BN relative to the graphene M point. These findings highlight the importance of considering twist-coupling effects in device fabrications and the potential of twist angles to design optoelectrical devices.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Ruijin Sun, Jun Deng, Yuxin Ma, Munan Hao, Xu Chen, Dezhong Meng, Changchun Zhao, Shixuan Du, Shifeng Jin, Xiaolong Chen
Summary: A new synthesis method was reported to successfully synthesize a layered ferromagnetic material (LiOH)(0.1)VS2, which shows strong anisotropic ferromagnetism below 40K. Calculations reveal that in-plane strains in a v3 v7VS2 superlattice can induce large magnetic anisotropic energy, which stabilizes the long-range ferromagnetic order. This finding provides a new approach to induce ferromagnetism in bulk TMD materials.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Ziyang Guo, Liyuan Qin, Shuai Zhao, Deqiu Wang, Xijuan Lv, Yujie Qiang, Wei Guo, Qinghai Shu, Y. Yao
Summary: By using ab initio molecular dynamics (AIMD) and density functional theory (DFT) calculations, this study investigates the mechanism of NTO induced metal corrosion. The results reveal that the acidity of NTO originates from its lower dehydrogenation barrier at the N4 site compared to the N1 site. NTO shows strong adsorption on Fe(110) in a nitro-dissociation manner, and the nitro-to-amino reaction can occur catalyzed by Fe(110) and hydrogen shuttling.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Rui-Zi Zhang, Jinbo Pan, Yu-Yang Zhang, Shixuan Du
Summary: We report on a class of auxetic 2D magnets, MCl2 (M = Ti, V, Mn, Fe, Co, Ni), which possess squared packed structure and exhibit in-plane auxetic effect. The occurence of such auxetic behavior is attributed to weak bond stiffness governed by electronic coupling between nearest-neighboring atoms. The magnetic properties in combination with the auxetic effect show potential for novel nanodevice applications.
Article
Chemistry, Analytical
Xianshuang Wang, Yage He, Ying Zhang, An Li, Xinyu Zhang, Xueyong Guo, Tonglai Zhang, Wei Guo, Ruibin Liu, Yugui Yao
Summary: This study focuses on the identification and classification of high explosives and organic compounds using nanosecond laser-induced plasma spectroscopy (LIPS). It determines the most discriminatory spectral regions for each material and reveals the role of carbon atoms in different emissions. The study also clarifies the quantitative correlations between emission intensity, oxygen balance, and aroma index. Classification models with high specificity and accuracy are established using well-selected spectral features and supervised classifiers.
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
(2023)
