Article
Physics, Multidisciplinary
M. Iqbal Bakti Utama, Roland J. Koch, Kyunghoon Lee, Nicolas Leconte, Hongyuan Li, Sihan Zhao, Lili Jiang, Jiayi Zhu, Kenji Watanabe, Takashi Taniguchi, Paul D. Ashby, Alexander Weber-Bargioni, Alex Zettl, Chris Jozwiak, Jeil Jung, Eli Rotenberg, Aaron Bostwick, Feng Wang
Summary: The study reveals that bilayer graphene can form a flat moire miniband at specific twisted angles, which is essential for the emergence of ordered phases. Through high-resolution angle-resolved photoemission spectroscopy, the visualization of this flat moire miniband in twisted bilayer graphene has been successfully achieved.
Article
Multidisciplinary Sciences
Dongfei Wang, De-Liang Bao, Qi Zheng, Chang-Tian Wang, Shiyong Wang, Peng Fan, Shantanu Mishra, Lei Tao, Yao Xiao, Li Huang, Xinliang Feng, Klaus Muellen, Yu-Yang Zhang, Roman Fasel, Pascal Ruffieux, Shixuan Du, Hong-Jun Gao
Summary: Stacking layered materials with nonzero interlayer twist angles, such as graphene and transitional metal dichalcogenides, has attracted attention due to their novel physical properties. In this study, we demonstrate that the edge states of twisted bilayer zigzag graphene nanoribbons (TBZGNRs) can be tuned by both the twist angle and the stacking offset. Strong edge state variations in the stacking region are revealed by density functional theory (DFT) calculations and scanning tunneling microscopy. Our work highlights the fundamental differences between 2D and 1D twistronics and encourages further investigation of twisted one-dimensional systems.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Can Liu, Zehui Li, Ruixi Qiao, Qinghe Wang, Zhibin Zhang, Fang Liu, Ziqi Zhou, Nianze Shang, Hongwei Fang, Meixiao Wang, Zhongkai Liu, Zuo Feng, Yang Cheng, Heng Wu, Dewei Gong, Song Liu, Zhensheng Zhang, Dingxin Zou, Ying Fu, Jun He, Hao Hong, Muhong Wu, Peng Gao, Ping-Heng Tan, Xinqiang Wang, Dapeng Yu, Enge Wang, Zhu-Jun Wang, Kaihui Liu
Summary: This study develops an effective strategy to grow centimeter-scale twisted bilayer graphene with arbitrary twist angles. The accuracy and consistency of the twist angles are demonstrated through comprehensive characterization techniques. This research provides an accessible route for the designed growth of large-scale two-dimensional twisted bilayers, laying the material foundation for future applications in twistronics at the integration level.
Article
Chemistry, Multidisciplinary
Yonghao Zhu, Oleg V. Prezhdo, Run Long, Wei-Hai Fang
Summary: Twisting angle affects electronic structure, interlayer coupling, and carrier dynamics in bilayer WS2, enhancing hole transfer but slowing down intervalley recombination. Breathing, in-plane and out-of-plane modes play vital roles in carrier transfer and recombination in twisted junctions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Yuji Araki, Pablo Solis-Fernandez, Yung-Chang Lin, Amane Motoyama, Kenji Kawahara, Mina Maruyama, Yanlin Gao, Rika Matsumoto, Kazu Suenaga, Susumu Okada, Hiroki Ago
Summary: This study investigates the twist angle dependence of intercalation of metal chlorides in bilayer graphene (BLG). It is found that high twist angle BLG is more favorable for intercalation due to weaker interlayer coupling. Scanning transmission electron microscope observations reveal the formation of various 2D structures through co-intercalation of AlCl3 and CuCl2 molecules. Moreover, high twist angle BLG exhibits lower sheet resistance before intercalation and intercalation further decreases the sheet resistance.
Article
Physics, Applied
Mari Ohfuchi, Shintaro Sato
Summary: This study focuses on the energetics and magnetism of symmetry-protected junction state arrays in graphene nanoribbons, finding that at least eight unit cells are required for antiferromagnetic states. Additionally, a proposed end structure is suggested to avoid disturbing the global topological properties, potentially offering new guidelines and challenges for graphene-based quantum computing.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Ruikang Dong, Xiaoshu Gong, Jiafu Yang, Yueming Sun, Jinlan Wang, Liang Ma
Summary: In this study, a theoretical strategy of bi-oriented step-guided nucleation and epitaxial growth is proposed for twist bilayer graphene. The presence of bi-oriented steps, which can be determined by adjacent steps, greatly reduces the free energy of the graphene with a matched twist angle, promoting its nucleation priority. By exploring all potential combinations of bi-steps on different epitaxial surfaces, 28 sets of bi-oriented steps with twist angles of 1.5 degrees - 30 degrees can be intentionally constructed.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
S. Candussio, M. Durnev, S. Slizovskiy, T. Joetten, J. Keil, V. V. Bel'kov, J. Yin, Y. Yang, S-K Son, A. Mishchenko, V Fal'ko, S. D. Ganichev
Summary: We report the resonant excitation of edge photocurrents in bilayer graphene under terahertz radiation and magnetic field. The observed interband and intraband transitions between Landau levels exhibit different resonant features, with the intraband transitions showing strong features traced to classical cyclotron resonance, while the interband transitions showing weaker features with quantum nature. The observed features in the photocurrent spectra agree with the semiclassical theory of the intraband edge photogalvanic effect, including Shubnikov-de-Haas oscillations at low temperatures.
Article
Nanoscience & Nanotechnology
Meng-Kai Lin, Jun Zhao, Joseph A. Hlevyack, T-C Chiang
Summary: This study reveals that adsorption of selenium vapor on bilayer graphene can create symmetric hybrid clone of the Dirac cones at the zone center. This mechanism provides a method to generate electronic features of scientific and technological interests through gentle surface modification via van der Waals adsorption.
NPJ 2D MATERIALS AND APPLICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Dharmendra Pant, Sandip Aryal, Subhasish Mandal, Ranjit Pati
Summary: Researchers have revealed ferromagnetism in twisted bilayer graphene nanoflex using first-principles approach, finding that the ferromagnetic phase appears irregularly between 0 and 30 degrees, rather than only at specific “magic angles”. The origin of electronic instability is attributed to aperiodic modulation of interlayer interaction in the nanoflex, resulting in the breaking of several higher-symmetry phases to lower the energy.
Article
Chemistry, Multidisciplinary
Teja Potocnik, Oliver Burton, Marcel Reutzel, David Schmitt, Jan Philipp Bange, Stefan Mathias, Fabian R. Geisenhof, R. Thomas Weitz, Linyuan Xin, Hannah J. Joyce, Stephan Hofmann, Jack A. Alexander-Webber
Summary: This study introduces spectroscopic ellipsometric contrast microscopy (SECM) as a tool for mapping twist angle disorder in optically resonant twisted bilayer graphene, confirming the accuracy and fast characterization of SECM.
Article
Chemistry, Physical
Antonija Grubisic-Cabo, Jimmy C. Kotsakidis, Yuefeng Yin, Anton Tadich, Matthew Haldon, Sean Solari, Iolanda Di Bernardo, Kevin M. Daniels, John Riley, Eric Huwald, Mark T. Edmonds, Rachael Myers-Ward, Nikhil V. Medhekar, D. Kurt Gaskill, Michael S. Fuhrer
Summary: The electronic structure of bilayer graphene was investigated using angle-resolved photoemission spectroscopy under high n-doping and extreme displacement fields. Intercalation of magnesium transformed the single massless Dirac band of monolayer graphene into the characteristic massive double-band Dirac spectrum of quasi-freestanding bilayer graphene. This resulted in an n-type doping of 2.1 x 10(14) cm(-2) and an extremely high displacement field of 2.6 V/nm, creating a significant gap of 0.36 eV at the Dirac point.
APPLIED SURFACE SCIENCE
(2021)
Article
Mechanics
Gianfranco Ulian, Daniele Moro, Giovanni Valdre
Summary: Graphene and MoS2 stacked composite materials have structural advantages and studies on electronic and optical properties have revealed a small direct band gap. The complex dielectric function and related properties in the visible-light spectral region of this composite material have shown significant variations.
COMPOSITE STRUCTURES
(2021)
Article
Physics, Applied
Shuo Han, Xianhua Nie, Shangzhi Gu, Wenyu Liu, Luchen Chen, Hao Ying, Le Wang, Zhihai Cheng, Li Zhao, Shanshan Chen
Summary: This study experimentally investigates the thermal conductivity of single-crystalline bilayer graphene as a function of interlayer twist angle and temperature. The results show that a slight twist angle can lead to a significant decrease in thermal conductivity. The study reveals the sensitivity of thermal conduction to the twist angle, providing insights into thermal transport in van der Waals bilayer systems.
APPLIED PHYSICS LETTERS
(2021)
Article
Optics
Seongju Ha, Nam Hun Park, Hyeonkyeong Kim, Jiseon Shin, Jungseok Choi, Sungmin Park, Ji-Yun Moon, Kwanbyung Chae, Jeil Jung, Jae-Hyun Lee, Youngdong Yoo, Ji-Yong Park, Kwang Jun Ahn, Dong-Il Yeom
Summary: Twisted bilayer graphene, with unconventional physical properties due to interlayer interactions, shows significantly enhanced third-order optical nonlinearity by changing the stacking angle, leading to a 60-fold increase in third-harmonic generation efficiency. Further investigation reveals a relation between gate-controlled THG enhancement and twist angle, suggesting a novel approach for enhancing optical nonlinearity in two-dimensional stacked material systems.
LIGHT-SCIENCE & APPLICATIONS
(2021)
Article
Chemistry, Physical
Qingmeng Gan, Ning Qin, Zhiqiang Li, Shuai Gu, Kemeng Liao, Kaili Zhang, Li Lu, Zhenghe Xu, Zhouguang Lu
Summary: This paper proposes a novel strategy of surface reconstruction for stabilizing nickel-rich layered oxide materials in lithium-ion batteries. By using facile plasma treatment, a homogeneous spinel layer is formed on the surface of LiNi0.8Co0.1Mn0.1O2 (NCM811), which enhances the capacity retention of the battery.
Article
Chemistry, Physical
Jiadong Zhou, Chao Zhu, Yao Zhou, Jichen Dong, Peiling Li, Zhaowei Zhang, Zhen Wang, Yung-Chang Lin, Jia Shi, Runwu Zhang, Yanzhen Zheng, Huimei Yu, Bijun Tang, Fucai Liu, Lin Wang, Liwei Liu, Gui-Bin Liu, Weida Hu, Yanfeng Gao, Haitao Yang, Weibo Gao, Li Lu, Yeliang Wang, Kazu Suenaga, Guangtong Liu, Feng Ding, Yugui Yao, Zheng Liu
Summary: This study reveals a competitive-chemical-reaction-based growth mechanism that allows for the growth of transition metal chalcogenides and transition metal phosphorous chalcogenides with different compositions and phases. It provides an interesting platform for the exploration of 2D TMPCs and TMCs.
Article
Chemistry, Multidisciplinary
Jichen Dong, Degong Ding, Chuanhong Jin, Yunqi Liu, Feng Ding
Summary: We present a systematic theoretical study on the CVD growth mechanism of MoS2 and propose a transition of growth from Mo-II edges to S-III edges and Mo-III edges by tuning the growth condition from Mo-rich to S-rich. This study provides a general guideline on theoretical studies of 2D crystals' growth mechanisms and deepens our understanding on the growth mechanism of multielement 2D crystals.
Article
Chemistry, Physical
Ziwei Xu, Feng Ding
Summary: This study reveals that the shape of the catalyst has an impact on the formation process of SWCNTs, and that using catalyst particles with higher curvature and catalytic reactions involving Pt adatom on the catalyst surface can promote the synthesis of SWCNTs.
Article
Engineering, Environmental
Shuai Gu, Jingjing Chen, Rui Hao, Xi Chen, Zhiqiang Wang, Iftikhar Hussain, Guiyu Liu, Kun Liu, Qingmeng Gan, Zhiqiang Li, Hao Guo, Yingzhi Li, He Huang, Kemeng Liao, Kaili Zhang, Zhouguang Lu
Summary: A novel bipolar polyimide COF with unique topology structure demonstrates high capacity and stability for dual-ion organic batteries. The COF stores Li+ ions and PF6- anions through the redox reactions of anionic imide radicals and cationic nitrogen-center radicals respectively. With optimized electrolyte, the COF exhibits high capacity and excellent cyclic performance.
CHEMICAL ENGINEERING JOURNAL
(2023)
Review
Engineering, Environmental
Iftikhar Hussain, Charmaine Lamiel, Muhammad Sufyan Javed, Muhammad Ahmad, Xi Chen, Sumanta Sahoo, Xiaoxia Ma, Majed A. Bajaber, Mohd Zahid Ansari, Kaili Zhang
Summary: The advancement of structured nanomaterials is crucial for the development of supercapacitor electrode materials. By evaluating various nanostructures, current challenges in electrode materials have been significantly improved. Nanomaterials with three-dimensional structures have been extensively explored due to their larger electrochemical active surface areas. This review summarizes the material development of hierarchical structures resembling earth-like and marine life-like morphology for supercapacitor electrode materials and discusses future ideas on sustainable production and assembly methods.
CHEMICAL ENGINEERING JOURNAL
(2023)
Review
Chemistry, Multidisciplinary
Umay Amara, Iftikhar Hussain, Muhmmad Ahmad, Khalid Mahmood, Kaili Zhang
Summary: MXene has emerged as a promising 2D material for various applications in the past decade. With its excellent metallic conductivity, optical absorbance, mechanical stability, heterogeneous electron transfer rate, and redox capability, MXene shows great potential in biosensing applications. Its hydrophilic nature, biocompatibility, antifouling, and anti-toxicity properties further enable its performance in vitro and in vivo analysis. This review comprehensively assesses and compiles the concept, operating principle, detailed mechanism, and characteristic properties of MXene, as well as breakthroughs in MXene fabrication and conjugation strategies for the development of unique electrochemical and optical biosensors. It also summarizes current challenges and suggests future directions. This review article sheds light on the development of MXene for biosensing and opens new opportunities for advanced translational applications of MXene bioassays.
Review
Chemistry, Physical
Sarmad Iqbal, Bushra Safdar, Iftikhar Hussain, Kaili Zhang, Christodoulos Chatzichristodoulou
Summary: Electrolytic hydrogen is crucial for producing green fuels and chemicals and maintaining energy balance in the future electricity grid. However, the sluggish kinetics of the oxygen evolution reaction (OER) impede its efficiency. Extensive research is being conducted to develop advanced OER electrocatalysts, including bulk and single-atom electrocatalysts (SACs).
ADVANCED ENERGY MATERIALS
(2023)
Article
Chemistry, Physical
Iftikhar Hussain, Mohd Zahid Ansari, Charmaine Lamiel, Tanveer Hussain, Muhammad Sufyan Javed, Thanayut Kaewmaraya, Muhammad Ahmad, Ning Qin, Kaili Zhang
Summary: The rational design of highly oriented and integrated heterostructures based on metal-organic framework (MOF)-derived carbon containing n-type metal chalcogenides (Zn-In-S/C) polyhedron and p-type metal oxide (CuO) nanowires was proposed. The p-type CuO nanowires were used as a stable scaffold to grow MOF-derived n-type Zn-In-S/C. The controlled and in situ fabricated Zn-In-S/C@CuO heterostructures provided a p-n heterojunction which enhanced the charge transfer, hence providing an improved overall electrochemical performance over its MOF and bare CuO counterpart. Coupled with density functional theory (DFT) calculations, the enhancement in the conductivity of the heterostructure was further verified. The symmetric supercapacitor device delivered an energy density of 7 Wh kg-1 at a power density of 4 kW kg-1. Overall, the theoretical and experimental investigation of the oriented in situ grown Zn-In-S/C@CuO heterojunction with better cycling stability and electrochemical activity could be a useful asset for energy storage devices.
ACS ENERGY LETTERS
(2023)
Review
Thermodynamics
Iftikhar Hussain, Charmaine Lamiel, Muhammad Sufyan Javed, Muhammad Ahmad, Sumanta Sahoo, Xi Chen, Ning Qin, Sarmad Iqbal, Shuai Gu, Yuxiang Li, Christodoulos Chatzichristodoulou, Kaili Zhang
Summary: MXene, a two-dimensional transition metal carbide, nitrides, and/or carbonitrides, shows great potential in various research fields due to its excellent conductivity, hydrophilicity, and abundant surface functional groups. However, challenges in aggregation and low stability greatly limit its applicability. MXenes can be synthesized through techniques such as exfoliation of MAX phases assisted by HF and nonHF materials, and bottom-up approaches utilizing vapor deposition and templating methods. MXene-based heterostructure composites have been investigated as potential nanomaterials for energy storage, and this article provides an overview of MXene synthesis and current developments in MXene-based heterostructure composites for electrochemical energy storage devices. Challenges and difficulties in the future design of MXene-based heterostructure composites are also discussed.
PROGRESS IN ENERGY AND COMBUSTION SCIENCE
(2023)
Article
Energy & Fuels
Muhammad Ahmad, Tehseen Nawaz, Iftikhar Hussain, Qudrat Ullah, Xi Chen, Rajat Walia, Shafqat Ali, Saikh Mohammad Wabaidur, Waqas Ul Arifeen, Kaili Zhang
Summary: Transition metal selenides have become a popular choice in supercapacitors due to their excellent electrochemical performance, low cost, and environmentally friendly nature. Through fine-tuning the solvothermal reaction temperature, the structural orientation of ternary Mg-Ni-Co selenide (MNCSe) was successfully demonstrated. The self-aligned star-like MNCSe-180 nanoflakes showed a high specific capacity of 299.16 mAh g-1 (1 A g-1) in an aqueous KOH electrolyte. A hybrid supercapacitor device based on this electrode design achieved a high energy density of 46.56 Wh kg-1 and a maximum power density of 5.9 kW kg-1. This work provides valuable insights for the synthesis of novel materials with capacitive properties in next-generation energy storage devices.
JOURNAL OF ENERGY STORAGE
(2023)
Review
Energy & Fuels
Irum Shaheen, Iftikhar Hussain, Taghazal Zahra, Muhammad Sufyan Javed, Syed Shoaib Ahmad Shah, Karim Khan, Muhammad Bilal Hanif, Mohammed A. Assiri, Zafar Said, Waqas Ul Arifeen, Bhargav Akkinepally, Kaili Zhang
Summary: This review discusses the sustainable synthesis approaches for metal oxide nanomaterials in supercapacitors, including their morphological, compositional, and supercapacitive properties. It covers the design and types of supercapacitors based on electrode materials, and comprehensively explains metal oxide-based pseudocapacitive/battery-type electrodes. The review aims to provide guidelines for the sustainable fabrication of metal oxide nanomaterial-based supercapacitors and explain their design and functioning.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Materials Science, Multidisciplinary
Wookhee Lee, Daniel Hedman, Jichen Dong, Leining Zhang, Zonghoon Lee, Sung Youb Kim, Feng Ding
Summary: It is necessary to consider the kink energy, which is the energy of the junction between armchair and zigzag sites, when accurately calculating the formation energy of graphene edges with various functional groups. The kink energies of graphene edges with different functional groups are all negative, indicating that kink formation stabilizes the chiral graphene edges.
Article
Chemistry, Physical
Xi Chen, Yu Tang, Zhibo Zhang, Muhammad Ahmad, Iftikhar Hussain, Tianyi Li, Si Lan, Kaili Zhang, Qi Liu
Summary: In this study, a strategy to construct a stable Li-conductive layer on the surface of single-crystalline Ni-rich cathode particles is reported, which significantly improves the Li-ion diffusion coefficients and suppresses surface phase transformation. The improved kinetics result in good durability and excellent rate capability of the single-crystalline cathode.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Review
Chemistry, Multidisciplinary
Xiao Kong, Chengrui Fu, Vladislav Gladkikh, Feng Ding
Summary: The review summarizes the shapes and growth/etching mechanisms of 2D islands in the chemical vapor deposition (CVD) process. It discusses various aspects including attachment-limited and diffusion-limited growth, etching, and merging of 2D materials. The review also explores the growth and etching of multilayered 2D islands during CVD, which is an ongoing topic of research.
