Article
Physics, Applied
Bing Zhao, Bogdan Karpiak, Anamul Md Hoque, Pallavi Dhagat, Saroj P. Dash
Summary: This study investigates heterostructure devices of Fe3GeTe2 (FGT) two-dimensional magnets with monolayer graphene. The FGT Hall-bar devices show robust ferromagnetism and strong perpendicular anisotropy at low temperatures. The electrical transport properties of FGT/graphene heterostructure devices exhibit weak temperature dependence in tunneling transport. These findings have significance for engineering spintronic devices based on vdW heterostructures.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Leihao Feng, Xi Zhang, Quan Zheng, Ya Nie, Gang Xiang
Summary: The structural and electronic properties of a two-dimensional SiAs2/GeAs2 van der Waals heterostructure and its applications have been investigated by first-principles calculations and Silvaco Atlas simulations. The stable heterostructure exhibits an indirect bandgap of 0.99 eV in type II band alignment, making it suitable for light detection and energy harvesting. By applying an appropriate electric field, it can exhibit a direct bandgap up to 0.66 eV. The results show that the band alignment of the heterostructure can be tuned between type II and type I for various applications.
Article
Chemistry, Multidisciplinary
Bing Zhao, Roselle Ngaloy, Sukanya Ghosh, Soheil Ershadrad, Rahul Gupta, Khadiza Ali, Anamul Md. Hoque, Bogdan Karpiak, Dmitrii Khokhriakov, Craig Polley, Balasubramanian Thiagarajan, Alexei Kalaboukhov, Peter Svedlindh, Biplab Sanyal, Saroj P. Dash
Summary: This article demonstrates the robust room-temperature operation of lateral spin-valve devices using the vdW ferromagnet Fe5GeTe2 in heterostructures with graphene. Spin-dynamics measurements reveal multidirectional spin polarization at the Fe5GeTe2/graphene interface. Density functional theory calculations and Monte Carlo simulations reveal significantly canted Fe magnetic moments in Fe5GeTe2 along with the presence of negative spin polarization at the interface. These findings open opportunities for vdW interface design and applications of vdW-magnet-based spintronic devices at ambient temperatures.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Wanhan Su, Sen Zhang, Chang Liu, Qianlei Tian, Xingqiang Liu, Kenli Li, Yawei Lv, Lei Liao, Xuming Zou
Summary: This study demonstrates a 2D PVK and ReS2 heterostructure with high sensitivity and broad spectral response. The strong interlayer coupling and large type-II band offsets contribute to the improved performance of the heterostructure, making it a promising candidate for self-driven photodetectors.
Article
Multidisciplinary Sciences
Long Zhang, Fengcheng Wu, Shaocong Hou, Zhe Zhang, Yu-Hsun Chou, Kenji Watanabe, Takashi Taniguchi, Stephen R. Forrest, Hui Deng
Summary: Controlling matter-light interactions with cavities is crucial in modern science and technology. By integrating MoSe2-WS2 heterobilayers in a microcavity, cooperative coupling between moire-lattice excitons and microcavity photons has been established, providing versatile control of both matter and light. This moire polariton system combines strong nonlinearity and microscopic-scale tuning of matter excitations, offering a platform to study collective phenomena from tunable arrays of quantum emitters.
Article
Chemistry, Physical
Bi Luo, Peng Wu, Jiafeng Zhang, Liang Cao, Chunhui Wang, Bin Lu, Bao Zhang, Xing Ou
Summary: A two-dimensional space confined strategy is proposed to construct van der Waals heterostructures for superior potassium-ion battery (PIB) anodes. The synergistic effects in the 2D heterostructure greatly enhance electron transportation and ions diffusion, while inhibiting polysulfide dissolution for increased structural durability. As a result, the synthesized C/MoS2/G anode demonstrates remarkable K-storage performance with high reversible capacity, excellent rate capability, and superior long-cycling stability.
Article
Chemistry, Analytical
Jianwei Gao, Chunhua Wang, Yujin Chu, Yingkuan Han, Yakun Gao, Yanhao Wang, Chao Wang, Hong Liu, Lin Han, Yu Zhang
Summary: A biosensor based on graphene oxide-graphene van der Waals heterostructure has been developed for rapid and accurate detection of SARS-CoV-2 proteins. The biosensor shows strong selectivity and high sensitivity, outperforming traditional biosensors.
Article
Chemistry, Multidisciplinary
Jingrun Ran, Hongping Zhang, Jiangtao Qu, Jieqiong Shan, Kenneth Davey, Julie M. Cairney, Liqiang Jing, Shi-Zhang Qiao
Summary: This study introduces a ReS2/In2ZnS4 2D/2D van der Waals heterostructure with highly promoted photocatalytic H-2-evolution rate, making it one of the most efficient In2ZnS4-based photocatalysts. Advanced characterizations and theoretical computations demonstrate that the interlayer electronic interaction and atomic-level S active centers within the structure collaboratively boost light-induced H-2 evolution.
Article
Engineering, Environmental
Ruozhen Wu, Kangkai Yan, Jinyun Zhao, Zhenghan Cai, Shaoju Jian, Liqing Qiu
Summary: 2D/2D van der Waals heterostructure is an effective approach for improving 2D layered nanomaterials' functions due to high-quality heterointerfaces. However, the influence of heterointerface quantity and quality on gas-sensing performance has been overlooked.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Wei Sun, Wenxuan Wang, Jiadong Zang, Hang Li, Guangbiao Zhang, Jianli Wang, Zhenxiang Cheng
Summary: This work demonstrates a complete Neel-type skyrmion-bimeron-ferromagnet phase transition in WTe2/CrCl3 bilayer van der Waals heterostructures, driven by the competition between out-of-plane magnetocrystalline anisotropy and magnetic dipole-dipole interaction. With the addition of a ferroelectric CuInP2S6 monolayer as a substrate, writing and erasing of skyrmions can be regulated using ferroelectric polarization. This study provides insight into a novel approach for the design and control of magnetic skyrmions on 2D van der Waals materials.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Physical
Yecheng Ma, Shan Lu, Xiaolei Dong, Gaorong Han, Zongping Chen, Yong Liu
Summary: In this study, the researchers analyzed the optical parameters of graphene/MoS2 vdW heterostructure using spectroscopic ellipsometry (SE) and investigated the influence of interlayer coupling on its photoelectric properties. The results provide valuable insights into the optical parameters and potential applications of vdW heterostructures in optoelectronics.
APPLIED SURFACE SCIENCE
(2022)
Review
Chemistry, Multidisciplinary
Hui-Lei Hou, Cosimo Anichini, Paolo Samori, Alejandro Criado, Maurizio Prato
Summary: In the past 15 years, 2D materials have revolutionized materials science and become powerful components for high-performance chemical sensors. By forming van der Waals heterostructures (VDWHs), the individual drawbacks of 2D materials can be overcome, leading to superior sensitivities, selectivity, and stability. This review discusses the latest developments in chemical sensors based on VDWHs of 2D materials, including sensing mechanisms and future directions with potential impact in environmental sciences and biomedical applications.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Vishakha Gupta, Rakshit Jain, Yafei Ren, Xiyue S. Zhang, Husain F. Alnaser, Amit Vashist, Vikram V. Deshpande, David A. Muller, Di Xiao, Taylor D. Sparks, Daniel C. Ralph
Summary: The advantages of mechanically stacked samples of van der Waals materials for controlling the surface state of a three-dimensional topological insulator are demonstrated. The interaction between the topological surface state and an adjacent magnet layer can be controlled, resulting in an observed anomalous Hall effect.
Article
Chemistry, Multidisciplinary
Gichang Noh, Hwayoung Song, Heenang Choi, Mingyu Kim, Jae Hwan Jeong, Yongjoon Lee, Min-Yeong Choi, Saeyoung Oh, Min-kyung Jo, Dong Yeon Woo, Yooyeon Jo, Eunpyo Park, Eoram Moon, Tae Soo Kim, Hyun-Jun Chai, Woong Huh, Chul-Ho Lee, Cheol-Joo Kim, Heejun Yang, Senugwoo Song, Hu Young Jeong, Yong-Sung Kim, Gwan-Hyoung Lee, Jongsun Lim, Chang Gyoun Kim, Taek-Mo Chung, Joon Young Kwak, Kibum Kang
Summary: This study introduces the two-dimensional layered Ge4Se9 as a new choice of insulating vdW material, which is stacked with MoS2 to fabricate vdW heterostructure devices with a large memory window. The research shows that the devices have good repeatability and low energy consumption, proving their potential in the field of artificial synapses.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Physical
Nikhilesh Maity, Pooja Srivastava, Himani Mishra, Ravindra Shinde, Abhishek Kumar Singh
Summary: This study demonstrates the generation of linearly polarized, anisotropic intra- and interlayer excitonic bound states in the transition metal monochalcogenide (TMC) GeSe/SnS van der Waals heterostructure, showing dramatic variation in excitonic energies and optical absorption spectrum under compressive/tensile biaxial strain. The changes in excitonic energies and optical band gap are attributed to the shift in effective dielectric constant and band dispersion upon the application of biaxial strain, showing potential applications in optoelectronics and optical quantum computers.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Physics, Condensed Matter
O. Steuer, D. Schwarz, M. Oehme, J. Schulze, R. Kudrawiec, I. A. Fischer, R. Heller, R. Huebner, M. M. Khan, Y. M. Georgiev, S. Zhou, M. Helm, S. Prucnal
Summary: In this article, strain and band-gap engineering in Ge1-x Sn (x) alloys grown on Ge virtual substrate using post-growth nanosecond pulsed laser melting (PLM) is presented. The initial in-plane compressive strain is removed, and the Ge0.89Sn0.11 layer becomes tensile strained for PLM energy densities higher than 0.5 J cm(-2). The crystalline quality and Sn-distribution in PLM-treated Ge0.89Sn0.11 layers are only slightly affected, and the change of the band structure after PLM is confirmed.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Chemistry, Multidisciplinary
Saikat Bag, Himadri Sekhar Sasmal, Sonu Pratap Chaudhary, Kaushik Dey, Dominic Blaette, Roman Guntermann, Yingying Zhang, Miroslav Poloz, Agnieszka Kuc, Ankita Shelke, Ratheesh K. Vijayaraghavan, Thalasseril G. Ajithkumar, Sayan Bhattacharyya, Thomas Heine, Thomas Bein, Rahul Banerjee
Summary: We successfully synthesized uniform covalent organic framework (COF) thin films using a solution-processable sphere transmutation process, which exhibited good crystallinity, porosity, and uniform thickness on a fluorine-doped tin oxide (FTO) surface. Four different COF thin films with different functional backbones were synthesized, and the TpEtBr COF film showed the lowest optical band gap and highest excited-state lifetime. All of the COF films exhibited significant photocurrent after illumination with visible light, indicating good photoactive characteristics. The out-of-plane photodetector device based on the TpEtBr COF thin film showed high photocurrent density and hole mobility, demonstrating the best photoactive properties.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Jiaye Jin, Toshiki Wulf, Marcel Jorewitz, Thomas Heine, Knut R. Asmis
Summary: The vibrational spectra of copper(I) cation-dihydrogen complexes Cu+(H-2)(4), Cu+(D-2)(4), and Cu+(D-2)(3)H-2 were studied using cryogenic ion trap vibrational spectroscopy and quantum chemical calculations. The IRPD spectra were assigned based on comparison to calculated IR spectra. The observed vibrational features indicate the excitations of dihydrogen stretching fundamentals and the interconversion of dihydrogen positions.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Yi Li, Juanmei Duan, Yonder Berencen, Rene Hubner, Hsu-Sheng Tsai, Chia-Nung Kuo, Chin Shan Lue, Manfred Helm, Shengqiang Zhou, Slawomir Prucnal
Summary: In this work, we fabricated vertical p-n heterojunctions made of p-type tin monoselenide (SnSe) and n-type tin diselenide (SnSe2) through NH3 plasma-assisted phase transformation. Optimal plasma parameters were determined for the full transformation of SnSe2 into SnSe within a few seconds. The crystal quality and topography of the heterostructures were characterized using micro-Raman spectroscopy and transmission electron microscopy, and the formation of a p-n junction was confirmed through current-voltage measurements.
NANOSCALE ADVANCES
(2023)
Article
Materials Science, Multidisciplinary
Florian M. Arnold, Alireza Ghasemifard, Agnieszka Kuc, Jens Kunstmann, Thomas Heine
Summary: Manipulating the twist angle between layers has a significant impact on the properties of layered two-dimensional crystals. In this study, the characteristics of twisted bilayer MoS2 were monitored as a function of the twist angle. Different structural regimes were identified, each with specific structural and electronic properties. The results showed the emergence of extended stacking domains, soliton networks, and superlattices, which contribute to exciting electronic effects.
Article
Multidisciplinary Sciences
Jonas Schabernack, Augusto Faria Oliveira, Thomas Heine, Cornelius Fischer
Summary: In deep geological repositories for nuclear waste, the surrounding rock formation acts as an essential barrier to prevent the migration of radionuclides. Phyllosilicates found in various potential host rocks have demonstrated high efficiency in sorbing radionuclides. This study investigates the energetic differences of surface sorption sites on nanotopographic structures and provides a mechanistic explanation for the heterogeneous sorption observed on mineral surfaces.
ADVANCED THEORY AND SIMULATIONS
(2023)
Article
Materials Science, Multidisciplinary
Kunie Ishioka, Alexej Pashkin, Christian Bernhard, Hrvoje Petek, Xin Yao, Jure Demsar
Summary: We investigate coherent lattice dynamics in optimally doped YBa2Cu3O7-delta driven by ultrashort near-infrared and near-ultraviolet pulses. Transient reflectivity experiments reveal Ag-symmetry phonon modes related to bending in the CuO2 planes and stretching at frequencies between 10 and 15 THz. The relative coherent phonon amplitudes are in stark contrast to the relative phonon intensities in the spontaneous Raman scattering spectrum, indicating mode-dependent contributions of Raman and non-Raman mechanisms to coherent phonon generation.
Article
Chemistry, Multidisciplinary
Xing Huang, Shuai Fu, Cong Lin, Yang Lu, Mingchao Wang, Peng Zhang, Chuanhui Huang, Zichao Li, Zhongquan Liao, Ye Zou, Jian Li, Shengqiang Zhou, Manfred Helm, Petko St Petkov, Thomas Heine, Mischa Bonn, Hai I. Wang, Xinliang Feng, Renhao Dong
Summary: This study demonstrates a strategy for synthesizing high-mobility semiconducting coordination polymers (c-CPs) using novel conjugated ligands with reduced symmetry. The synthesized c-CPs exhibit a small band gap, dispersive energy bands, and high charge carrier mobilities, outperforming previously reported conductive coordination polymers. This molecular design strategy lays the foundation for achieving high-performance c-CP-based (opto-)electronics.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Chuanhui Huang, Weiming Sun, Yingxue Jin, Quanquan Guo, David Muecke, Xingyuan Chu, Zhongquan Liao, Naisa Chandrasekhar, Xing Huang, Yang Lu, Guangbo Chen, Mingchao Wang, Jinxin Liu, Geping Zhang, Minghao Yu, Haoyuan Qi, Ute Kaiser, Gang Xu, Xinliang Feng, Renhao Dong
Summary: Two-dimensional conjugated metal-organic frameworks (2D c-MOFs) are a subclass of layer-stacked crystalline coordination polymers that possess both porous and conductive properties, making them suitable for energy and electronic device applications. Controlled synthesis of hierarchically nanostructured 2D c-MOFs with customized morphologies and dimensions is essential to fully utilize their electronic properties and structural features. A template strategy has been developed to achieve this via insulating MOFs-to-c-MOFs transformations, resulting in higher surface areas and improved access to active sites. The hierarchically nanostructured 2D c-MOFs show superior performance in electrical properties related applications, such as supercapacitors and gas sensors, with significant improvements in specific capacity and response intensity compared to bulk-type c-MOFs.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Anupam Prasoon, Hyejung Yang, Mike Hambsch, Nguyen Ngan Nguyen, Sein Chung, Alina Mueller, Zhiyong Wang, Tianshu Lan, Philippe Fontaine, Thomas D. Kuehne, Kilwon Cho, Ali Shaygan Nia, Stefan C. B. Mannsfeld, Renhao Dong, Xinliang Feng
Summary: This study demonstrates an efficient on-water surface synthesis of crystalline monolayer 2D polyimide (2DPI) with excellent stability and coverage. By combining with exfoliated MoS2, innovative organic-inorganic hybrid van der Waals heterostructures (vdWHs) are fabricated, facilitating remarkable charge transfer and improved electron mobility.
COMMUNICATIONS CHEMISTRY
(2023)
Article
Chemistry, Physical
Preetam Dacha, Mike Hambsch, Darius Pohl, Katherina Haase, Markus Loeffler, Tianshu Lan, Xinliang Feng, Bernd Rellinghaus, Stefan C. B. Mannsfeld
Summary: A solution shearing procedure is reported for fabricating micro/nano wires from a diketopyrrolopyrrole (DPP)-based polymer. The as-fabricated wires exhibit a high degree of molecular orientation and enhanced electrical performance in single wire Organic Field Effect Transistors (OFETs).
Article
Chemistry, Multidisciplinary
Xipeng Shu, Liang Hu, Thomas Heine, Yu Jing
Summary: By introducing pyridinic N in the skeletons of carbonyl aromatic compounds, the electrochemical performance can be significantly improved, making them promising organic cathode materials for lithium-ion batteries.
Article
Chemistry, Multidisciplinary
Kejun Liu, Julien Rehault, Baokun Liang, Mike Hambsch, Yingying Zhang, Sezer Seckin, Yunxia Zhou, Rishi Shivhare, Peng Zhang, Miroslav Polozij, Tobias A. F. Koenig, Haoyuan Qi, Shengqiang Zhou, Andreas Fery, Stefan C. B. Mannsfeld, Ute Kaiser, Thomas Heine, Natalie Banerji, Renhao Dong, Xinliang Feng
Summary: This study reports the synthesis of a novel crystalline q2D polypyrrole film at the air/H2SO4 interface. The film exhibits a unique molecular structure and charge transport properties.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Ivan Fotev, Stephan Winnerl, Saicharan Aswartham, Sabine Wurmehl, Bernd Buechner, Harald Schneider, Manfred Helm, Alexej Pashkin
Summary: In this study, the suppression of spin density wave (SDW) order in BaFe2As2 under pressure was investigated using optical pump-probe technique. The results show that the pressure-induced suppression of SDW order at low temperature occurs gradually, in contrast to the thermally induced SDW transition. This suggests that the pressure-driven quantum phase transition in BaFe2As2 (and probably other iron pnictides) is continuous and it is caused by the gradual worsening of the Fermi-surface nesting conditions.