Article
Materials Science, Multidisciplinary
T. J. Hicken, Z. Hawkhead, M. N. Wilson, B. M. Huddart, A. E. Hall, G. Balakrishnan, C. Wang, F. L. Pratt, S. J. Clark, T. Lancaster
Summary: In this study, electronic structure calculations were used to explain the low-temperature electronic and magnetic properties of Cr1/3MS2. The materials were found to be half metals with a gaplike feature in the density of states. The existence of this gap was confirmed through magnetometry measurements, and dynamic spin fluctuations driven by excitations across this gap were observed.
Article
Materials Science, Multidisciplinary
Rui Ma, Duncan S. Sutherland, Yumeng Shi
Summary: Transition metal dichalcogenides (TMD), with outstanding optical characteristics and an absence of crystal inversion symmetry, are frequently used in studies of nonlinear optics (NLO) for harmonic generation. By fabricating TMD into heterostructures to enhance and manipulate the response, the performance in harmonic generation has been improved. The focus on heterostructure studies to enhance and manipulate the response represents core issues for devices and applications.
Article
Chemistry, Multidisciplinary
Fang Li, Rui Tao, Banglin Cao, Lei Yang, Zegao Wang
Summary: This study synthesized large-area PtS films and fabricated MoS2/PtS p-n heterojunction, discussing its energy band structure and photoresponse characteristics, achieving improved room temperature photodetection performance.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Vladislav Buravets, Frantisek Hosek, Ladislav Lapcak, Elena Miliutina, Petr Sajdl, Roman Elashnikov, Vaclav Svorcik, Oleksiy Lyutakov
Summary: In this study, a novel, simple, and scalable method for the synthesis of tantalum disulfide (TaS2) is reported, using CS2 as a sulfurizing agent and Ta2O5 as a metal precursor. The structure of the created TaS2 flakes was analyzed, and a tuning between 1T (metallic) and 3R (semiconductor) phases was achieved by varying the reaction conditions. The electrocatalytic activity of the synthesized materials was significantly enhanced after electrochemical self-activation, reaching a level comparable to that of Pt. This work provides a scalable and simple synthesis method for transition-metal sulfides that could replace platinum catalysts in water splitting technology.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
Chloe F. Doiron, Jacob B. Khurgin, Gururaj Naik
Summary: This article discusses the potential applications of high refractive index dielectrics in nanophotonics and addresses the challenge of lacking a complete material library by introducing the concept of super-Mossian dielectrics. The specific example of iron pyrite is used to illustrate the discussion, and the local dielectric resonances in iron pyrite nanoresonators are experimentally observed.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Physical
Soungmin Bae, Tae Young Jeong, Hannes Raebiger, Ki-Ju Yee, Yong-Hoon Kim
Summary: We present spectroscopic evidence for the ultrafast trapping of band edge excitons at defects and the subsequent generation of defect-localized coherent phonons (CPs) in monolayer MoSe2. Our time-resolved pump-probe spectroscopy on the sub-picosecond time scale detects localized CPs only from the ultrafast exciton trapping at shallow traps. Based on density functional calculations, we identify the origins of deep and shallow traps as Se vacancy and oxygen molecule adsorbed on a Se vacancy, respectively. Our work establishes the correlations between defect-induced ultrafast exciton trapping and the generation of defect-localized CPs, providing new opportunities for engineering photoexcited carriers in two-dimensional materials through lattice defects.
NANOSCALE HORIZONS
(2023)
Article
Chemistry, Multidisciplinary
Ahmad Bagheri, Sebastiano Bellani, Hossein Beydaghi, Matilde Eredia, Leyla Najafi, Gabriele Bianca, Marilena Isabella Zappia, Milad Safarpour, Maedeh Najafi, Elisa Mantero, Zdenek Sofer, Guorong Hou, Vittorio Pellegrini, Xinliang Feng, Francesco Bonaccorso
Summary: Efficient and durable flexible solid-state supercapacitors are essential for portable and wearable electronics. This study proposes an innovative composite solid-state electrolyte by incorporating metallic two-dimensional group-5 transition metal dichalcogenides into a sulfonated poly(ether ether ketone) polymeric matrix. The resulting solid-state electrolyte exhibits high proton conductivity and mechanical stability, making it ideal for use in solid-state supercapacitors.
Article
Physics, Applied
Kishan Lal Kumawat, Pius Augustine, Deependra Kumar Singh, Karuna Kar Nanda, Saluru Baba Krupanidhi
Summary: A MoS2/ZnO heterostructure-based photodetector with bias-dependent switchable spectral response is demonstrated. By vertically stacking a low-band-gap MoS2 thin film on top of a high-band-gap ZnO film and modulating the applied bias, fine discrimination between visible and near-infrared light is achieved.
PHYSICAL REVIEW APPLIED
(2022)
Article
Chemistry, Physical
Sonu Prasad Keshri, Swapan K. Pati, Amal Medhi
Summary: In this study, we calculate the carrier mobility of monolayer HfSe2 using density functional perturbation theory and Boltzmann transport equation, and accurately determine the experimental value. Compared to the previously used deformation potential model, we find that the strong electron-optical phonon interaction is one of the reasons for the low mobility. The results also show that the spin-orbit coupling significantly affects the mobility and scattering rates.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Dunren He, Yaocheng Yang, Yuan Zhou, Juanyong Wan, Heao Wang, Xi Fan, Qi Li, Huihui Huang
Summary: A high-performance water vapour energy harvester based on flexible MoS2 nanosheets with phase-gradient properties is reported, providing substantial voltage and current output with low internal resistance. This novel hydrovoltaic device, due to its flexible, safe, lightweight, and easily producible advantages, can be designed as a self-powered human-breathing monitor integrated in disposable masks. Output voltage can be further enhanced for powering commercial electronic devices through the serial connections of phase-engineered MoS2 sponges.
Article
Chemistry, Multidisciplinary
Min-Hye Jeong, Hyun-Soo Ra, Sang-Hyeon Lee, Do-Hyun Kwak, Jongtae Ahn, Won Seok Yun, JaeDong Lee, Weon-Sik Chae, Do Kyung Hwang, Jong-Soo Lee
Summary: This study proposes periodically arrayed nanopore structures (PANS) to improve the efficiency of multilayered p-WSe2/n-MoS2 phototransistors. Experiments and theoretical calculations reveal that heterojunction devices with PANS exhibit higher responsivity and detectivity, representing a significant step towards next-generation optoelectronic applications.
ADVANCED MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Minglei Sun, Michele Re Fiorentin, Udo Schwingenschlogl, Maurizia Palummo
Summary: Semiconducting two-dimensional materials with the chemical formula MoSi2X4 (X = N, P, or As) were studied using atomistic simulations. It was found that MoSi2X4 has promising optical properties, such as the absence of lateral valleys, small exciton binding energies, and long radiative lifetimes, making it suitable for applications in optoelectronic devices.
NPJ 2D MATERIALS AND APPLICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Tsung-Han Tsai, Anup Kumar Sahoo, Hong-Kai Syu, Yi-Chieh Wu, Meng-Yu Tsai, Ming-Deng Siao, Yueh-Chiang Yang, Yen-Fu Lin, Rai-Shung Liu, Po-Wen Chiu
Summary: In this study, a composite photodetector consisting of graphene-contacted monolayer WS2 stacked atop dispersed WSe2 nanodots was developed, achieving high responsivity, fast response time, and high gain. By utilizing the differences between photoexcited electrons and holes, a photogain was achieved through electron recirculation across the WS2 channel with trapped holes remaining in the WSe2 nanodots. Performance enhancement was attributed to the use of CVD-grown WSe2 nanocrystals as a photosensitizer, reducing contact barrier and providing rapid excitonic dynamics through the size-controllable WSe2/WS2 heterojunction.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Jennifer Schmeink, Vladislav Musytschuk, Erik Pollmann, Stephan Sleziona, Andre Maas, Peter Kratzer, Marika Schleberger
Summary: With the study of Janus monolayer transition metal dichalcogenides, research on two-dimensional materials is advancing into new areas. In this work, we synthesize MoSSe monolayers and compare their Raman signatures with density functional theory calculations to infer limits for strain and doping levels. This reference data can be applied to estimate strain and doping in other MoSSe Janus samples, providing a reliable tool for future work.
Article
Chemistry, Physical
Yang Ding, Renxian Qi, Chenglin Wang, Qianqian Wu, Haozhe Zhang, Xiumei Zhang, Liangliang Lin, Zhengyang Cai, Shaoqing Xiao, Xiaofeng Gu, Haiyan Nan
Summary: This research proposes a novel method for creating 1T-2H-1T MoTe2 optoelectronic devices using oxygen mild plasma preparation, which improves the performance of the devices.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Polymer Science
Wen Qian, Shuo Sun, Tyler J. Johnson, Charles Nguyen, Stephen Ducharme, Joseph A. Turner
Summary: This paper investigates the correlations between the chain orientation, anisotropy, and dynamic nanomechanical properties of PVDF copolymers using a combination of infrared atomic force microscopy, contact-resonance atomic force microscopy, scanning electron microscopy, and high resolution transmission electron microscopy. The results reveal a quick, effective, and nondestructive method to understand the formation mechanisms and optimize the organization of electroactive polymers.
Article
Physics, Applied
Xuegang Chen, Qiuchen Wu, Le Zhang, Yifei Hao, Myung-Geun Han, Yimei Zhu, Xia Hong
Summary: In this study, we investigate the unconventional magnetotransport properties of NiCo2O4 thin films. The results show that even at ultrathin film thickness, NiCo2O4 films still exhibit strong perpendicular magnetic anisotropy, which is crucial for nanoscale spintronic applications. The changes in magnetotransport properties can be attributed to the competing effects between impurity scattering and band intrinsic Berry curvature.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Applied
Xiaoshan Xu, Corbyn Mellinger, Zhi Gang Cheng, Xuegang Chen, Xia Hong
Summary: This Perspective article summarizes the recent advances in epitaxial NiCo2O4 thin films, focusing on their unusual magnetic and transport properties in relation to crystal structure and electronic structure. The study reveals the presence of perpendicular magnetic anisotropy and linear magnetoresistance in NiCo2O4 films, providing a foundation for the design of nanoscale spintronic devices.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Physics, Applied
Hanying Chen, Tianlin Li, Yifei Hao, Anil Rajapitamahuni, Zhiyong Xiao, Stefan Schoeche, Mathias Schubert, Xia Hong
Summary: We report the effect of remote surface optical (RSO) phonon scattering on carrier mobility in ferroelectric-gated monolayer graphene. Through the fabrication of monolayer graphene transistors gated by epitaxial (001) Ba0.6Sr0.4TiO3 films, we achieved a field effect mobility of up to 23,000 cm(2)V-1 s(-1). We also discovered that switching ferroelectric polarization can nonvolatilely modulate the resistance and quantum Hall effect in graphene at low temperatures. Using ellipsometry spectroscopy, we extracted the RSO phonon frequencies in Ba0.6Sr0.4TiO3.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Jingfeng Song, Yubo Qi, Zhiyong Xiao, Kun Wang, Dawei Li, Seung-Hyun Kim, Angus Kingon, Andrew M. Rappe, Xia Hong
Summary: In this work, we demonstrate steep slope switching in MoS2 transistors back-gated by single-layer polycrystalline PbZr0.35Ti0.65O3, achieving current switching ratios up to 8 x 10(6) within an ultra-low gate voltage window and subthreshold swing as low as 9.7 mV decade(-1). The dominant role of metastable polar states within domain walls in enabling the negative capacitance mode is revealed by theoretical modeling, providing a hysteresis-free mechanism for low-power 2D nanoelectronics.
NPJ 2D MATERIALS AND APPLICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Xun Li, Seung-Hwan Do, Jiaqiang Yan, Michael A. McGuire, Garrett E. Granroth, Sai Mu, Tom Berlijn, Valentino R. Cooper, Andrew D. Christianson, Lucas Lindsay
Summary: Phonon-derived behaviors play an important role in indicating novel phenomena in transition metal trihalides. This study explores the vibrational properties of the ferromagnetic honeycomb lattice material CrCl3 and introduces an efficient dynamic method for understanding phonon behaviors in various materials. The findings provide insights into spin-lattice couplings and open new avenues for studying phonons in layered magnets.
Article
Chemistry, Multidisciplinary
Dawei Li, Xi Huang, Qiuchen Wu, Le Zhang, Yongfeng Lu, Xia Hong
Summary: This study demonstrates the modulation of the amplitude and polarization of second harmonic generation (SHG) signal in monolayer MoS2 by interfacing it with PZT thin films and membranes. The control of the SHG light polarization is achieved through ferroelectric domain patterning, utilizing the interfacial coupling between MoS2 and PZT. This work provides a new material platform for reconfigurable design of light polarization at the nanoscale.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Composites
Jean-Francois Silvain, Benjamin Thomas, Loic Constantin, Mael Pontoreau, Yongfeng Lu, Jean-Luc Grosseau-Poussard, Guillaume Lacombe
Summary: The green MLM technique allows for the homogeneous mixing of silver and graphene, leading to improved thermal conductivity and mechanical properties of metal matrix composites (MMCs).
JOURNAL OF COMPOSITE MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Jia Wang, Zahra Ahmadi, David Lujan, Jeongheon Choe, Takashi Taniguchi, Kenji Watanabe, Xiaoqin Li, Jeffrey E. E. Shield, Xia Hong
Summary: CrX3 (X = I, Br, and Cl) magnets are highly tunable and promising for developing novel 2D spintronic devices. This study reports the successful growth of high quality monolayer CrCl3 flakes using physical vapor transport technique, demonstrating their magnetic properties and stability.
Editorial Material
Physics, Applied
Wenjuan Zhu, Xia Hong, Peide D. Ye, Yi Gu
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Instruments & Instrumentation
Yibo Wang, Sajib Kumar Saha, Tianlin Li, Yanwei Xiong, Kyle Wilkin, Anil Adhikari, Michael Loes, Jehad Abourahma, Xia Hong, Shireen Adenwalla, Alexander Sinitskii, Martin Centurion
Summary: We modified a gas phase ultrafast electron diffraction (UED) instrument to conduct experiments on both gas and condensed matter targets. The modified instrument demonstrated sub-picosecond time-resolved experiments with solid state samples. By using a hybrid DC-RF acceleration structure, femtosecond electron pulses are delivered to the target synchronized with femtosecond laser pulses. The new system allows for transmission UED on thin solid samples, as well as cooling samples to cryogenic temperatures and carrying out time-resolved measurements. The cooling capability was tested on 1T-TaS2 for diffraction patterns of temperature dependent charge density waves, and the time-resolved capability was verified by capturing dynamics in photoexcited single-crystal gold.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Article
Chemistry, Multidisciplinary
Kun Wang, Du Li, Jia Wang, Yifei Hao, Hailey Anderson, Li Yang, Xia Hong
Summary: Researchers found that the ferroelectricity, piezoelectricity, and polar alignment of CuInP2S6 can be enhanced in the ultrathin limit when it is interfaced with ferroelectric oxide PbZr0.2Ti0.8O3 films. This enhancement is attributed to the interface-mediated structure distortion in CuInP2S6. The study provides an effective material strategy to engineer the polar properties of CuInP2S6 for flexible nanoelectronic, optoelectronic, and mechanical applications.
Article
Chemistry, Physical
Nan Li, Xi Huang, Haoyu Dong, Bin Duan, Qiuchi Zhu, Aofei Mao, Peizi Li, Bai Cui, Jean-Francois Silvain, Yongfeng Lu
Summary: In this study, nanostructures were fabricated on silicon substrates using ultraviolet femtosecond lasers, and these nanostructures were used as SERS-active substrates. It was found that under certain laser parameters, nanoripple structures can achieve high SERS enhancement factors. Furthermore, nanoripple structures and SERS effects were explored on other materials. The effectiveness of the SERS substrates was demonstrated through applications with Sudan I, small extracellular vesicles, and glucose.
APPLIED SURFACE SCIENCE
(2023)
Editorial Material
Chemistry, Physical
Xia Hong
Summary: Piezoresponse microscopy and spectroscopy demonstrate the critical role of surface electrochemistry in stabilizing and controlling ferroelectricity in doped hafnia.
Article
Materials Science, Composites
Antoine Bident, Florence Delange, Christine Labrugere, Catherine Debiemme-Chouvy, Yongfeng Lu, Jean-Francois Silvain
Summary: This study presents a novel approach to fabricating a copper/graphene composite using a powder metallurgy-based method. By controlling the interface and ensuring the dispersion of the reinforcement, the hardness of the material was successfully improved. The reduction in electrical resistance varied for different types of copper materials, with potential for further enhancing the electrical properties.
JOURNAL OF COMPOSITE MATERIALS
(2023)