Article
Multidisciplinary Sciences
Zheyi Lu, Yang Chen, Weiqi Dang, Lingan Kong, Quanyang Tao, Likuan Ma, Donglin Lu, Liting Liu, Wanying Li, Zhiwei Li, Xiao Liu, Yiliu Wang, Xidong Duan, Lei Liao, Yuan Liu
Summary: A dry dielectric integration strategy enables the transfer of wafer-scale and high-kappa dielectrics on top of 2D semiconductors. An ultra-thin buffer layer is used to pre-deposit sub-3 nm thin Al2O3 or HfO2 dielectrics, which are then mechanically dry-transferred on top of MoS2 monolayers. The transferred ultra-thin dielectric film exhibits wafer-scale flatness and uniformity without any cracks, showing high capacitance, low leakage currents, and excellent transistor properties.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Yuting Chen, Yunlong Tang, Fenghui Gong, Bo Wu, Mengjiao Han, Minjie Zou, Yanpeng Feng, Yujia Wang, Yinlian Zhu, Xiuliang Ma
Summary: Screw dislocation is important for understanding plastic deformation and properties of materials. Direct observations of large-scale screw dislocation grids in oxide heteroepitaxies provide insights into their structures and effects on shear strains, suggesting a practical platform for studying screw dislocations.
Article
Nanoscience & Nanotechnology
Hae Won Cho, Pavan Pujar, Minsu Choi, Seunghun Kang, Seongin Hong, Junwoo Park, Seungho Baek, Yunseok Kim, Jaichan Lee, Sunkook Kim
Summary: The direct growth of polar orthorhombic phase in Hf0.5Zr0.5O2 (HZO) thin films using Pulsed Laser Deposition (PLD) has been reported. The PLD-HZO technique, integrated with HfO2 dielectric, has shown promising results for low power integrated digital/analog circuits.
NPJ 2D MATERIALS AND APPLICATIONS
(2021)
Article
Materials Science, Multidisciplinary
S. Y. Liu, G. J. Liu, C. Yu, S. Lippmann, Y. F. Zhu, Q. Jiang
Summary: The paper investigated the effect of heat treatment on the oxidation resistance (OR) of Mg alloyed by CaO with different weight percentages. The experiment found that heat treatment at 400 degrees C led to significantly improved OR, particularly for Mg alloy with 3% CaO. The improvement in OR is attributed to the formation of a uniform and dense protective layer during the heat treatment.
Article
Materials Science, Coatings & Films
Ghewa Akiki, Mathieu Fregnaux, Ileana Florea, Pavel Bulkin, Dmitri Daineka, Sergej Filonovich, Muriel Bouttemy, Erik Johnson
Summary: The study observed silicon deposition on SiOxNy, but not on AlOx or Al surfaces under the same plasma conditions. The silicon deposited on SiOxNy had a microcrystalline structure. Fluorine was detected on the AlOx surface, suggesting the formation of Al-F bonds blocking silicon deposition. Increasing electrode temperature or RF plasma power allowed deposition on AlOx surfaces, leading to a loss of selectivity.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2021)
Article
Chemistry, Physical
Siwon Lee, Chao Lin, Seunghyun Kim, Xinyu Mao, Taeho Kim, Sang-Joon Kim, Raymond J. Gorte, WooChul Jung
Summary: The influence of manganese oxide on CO oxidation over Pt catalysts was investigated. MnOx modification improved catalyst durability and CO oxidation rates by creating active Pt-MnOx interfacial sites. Despite suppressed CO adsorption after high-temperature calcination, TEM showed uniform coverage of Pt by a thin film of MnOx.
Article
Chemistry, Physical
Noemi Leick, Nicholas A. Strange, Andreas Schneemann, Vitalie Stavila, Karl Gross, Nancy Washton, Amy Settle, Madison B. Martinez, Thomas Gennett, Steven T. Christensen
Summary: This study utilizes nanoencapsulation and chemical additives simultaneously to modify borohydrides by using atomic layer deposition (ALD). The use of trimethylaluminum and water in the ALD process significantly improves the low-temperature H2 capacity and desorption kinetics of magnesium borohydride, while suppressing the release of diborane. These results suggest the potential of ALD as a method to functionalize solid-state H2 storage materials.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Shuangbao Wang, Zejian Dong, Lifeng Zhang, Panagiotis Tsiakaras, Pei Kang Shen, Langli Luo
Summary: The initial growth mode of oxide on alloy is crucial for the development of protective oxide scales on metals and alloys, but the specific atomistic mechanisms governing this growth remain unclear. By using environmental transmission electron microscopy and first-principles calculations, researchers have elucidated three different oxide growth modes of initial NiO islands on Ni-Cr alloy upon oxidation by O-2, showing that oxide growth is sensitive to local mass transport and kinetically controlled. This concept provides insights into oxide formation and has significant implications in material and chemical processes involving oxygen gas.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Mirine Leem, Deokjoon Eom, Heesoo Lee, Kwangwuk Park, Kwangsik Jeong, Hyoungsub Kim
Summary: In this study, HZO films were grown directly on single-crystalline MoS2 flakes using ALD with H2O or O3 oxidants. The O3-based ALD process oxidizes the MoS2 surface at the atomic layer level and facilitates the conformal deposition of an HZO film without surface treatment of MoS2. Annealing the O3-based HZO film significantly improves the ferroelectric properties, but also leads to diffusion of S, Hf, Zr, and O towards the Mo layer, reducing the weak HZO bonds.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Sonja Stefanovic, Negar Gheshlaghi, David Zanders, Ivan Kundrata, Baolin Zhao, Maissa K. S. Barr, Marcus Halik, Anjana Devi, Julien Bachmann
Summary: Area-selective atomic layer deposition (AS-ALD) is a bottom-up nanofabrication method that delivers single atoms from a molecular precursor. It offers advantages over lithography in terms of cost, resistance, and equipment prerequisites, but requires pre-patterned substrates and has limited selectivity and substrate choices. These challenges can be overcome with direct patterning using atomic-layer additive manufacturing (ALAM), which enables direct patterning instead of blanket coating. A functional thin-film transistor was created using ALAM-deposited ZnO and characterized.
Article
Chemistry, Physical
Jonathan L. Partridge, Aziz I. Abdulagatov, Varun Sharma, Jessica A. Murdzek, Andrew Cavanagh, Steven M. George
Summary: Thermal atomic layer etching (ALE) of CoO was demonstrated using sequential exposures of acetylacetone (Hacac) and ozone (O3). The surface reactions involved the removal of CoO by Hacac and the elimination of carbon residue by ozone. In situ spectroscopic ellipsometry showed a linear decrease in CoO film thickness with etch rate of 0.43 & ANGS;/cycle at 250 degrees C. The CoO film underwent changes in oxidation state and crystal structure during each reactant exposure. Ex situ grazing incidence X-ray diffraction (GIXRD) and X-ray photoelectron spectroscopy (XPS) confirmed the oxidation state of different cobalt oxides. Quadrupole mass spectrometry and atomic force microscopy measurements also provided insights into the etching process and surface roughness reduction during CoO ALE.
APPLIED SURFACE SCIENCE
(2023)
Article
Multidisciplinary Sciences
Hao Li, Ziheng Zhou, Wangyu Sun, Michael Lobet, Nader Engheta, Inigo Liberal, Yue Li
Summary: This paper reports experimental observation of electromagnetic power flow in a near-zero-index medium. The observed distribution of power flow exhibits characteristics similar to an ideal fluid. The results provide important insights into the development of ideal electromagnetic fluids and offer a tool to explore the subwavelength behavior of near-zero-index media.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
Jianwei Jiang, Sohee Choi, Jaehyun Oh, Jihyun Choi, Ho-Jung Sun, Sungho Yoon
Summary: This article introduces a nonclassical and highly effective method for synthesizing mononuclear N,O-chelate zirconium complexes, which utilizes the ring-opening insertion of epoxide into zirconium complexes at room temperature. Experimental results demonstrate that the produced precursor complex enables satisfactory growth rate of ZrO2 in ALD.
DALTON TRANSACTIONS
(2022)
Article
Optics
Jiahong Zhong, Cheng Zeng, Juan Yu, Lingkai Cao, Junnan Ding, Zongwen Liu, Yanping Liu
Summary: Rhenium disulfide (ReS2) has been identified as a promising material for future optoelectric applications due to its exceptional properties. A polarization-sensitive photodetector based on suspended ReS2 has been demonstrated with improved mobility, response time, and sensitivity, offering a more efficient approach for enhancing the performance of ReS2-based photodetectors.
Article
Physics, Applied
Virgil Guillon, Benoit Riou, Jerome Billoue, Thomas Defforge, Pascal Gardes, Micka Bah, Gael Gautier
Summary: In this study, the nanolamination of a ZrO2 insulator by Al2O3 was investigated for metal insulator metal capacitor applications. The results showed that increasing the number of Al2O3 layers led to a significant decrease in capacitance density, except when amorphous transition occurred, where a local maximum capacitance was obtained.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Zhonggang Liu, Dongzhen Lu, Wei Wang, Liguo Yue, Junlu Zhu, Ligong Zhao, He Zheng, Jianbo Wang, Yunyong Li
Summary: This study develops a high-density Ti3C2Tx MXene and graphene dual-encapsulated Si monolith anode for lithium-ion batteries. The anode exhibits ultrahigh volumetric capacity, superior long lifespan, and large areal capacity due to its dual-encapsulated Si architecture and 3D conductive and elastic networks of MXene and graphene. The integration of a dual-encapsulated strategy and dense-structure engineering offers a simple and feasible approach to enhance the volumetric and areal capacity of alloy-based anodes.
Article
Materials Science, Multidisciplinary
Ying Zhang, Yuxuan Hou, He Zheng, Ligong Zhao, Shuangfeng Jia, Kaixuan Li, Huayu Peng, Peili Zhao, Lei Li, Weiwei Meng, Renhui Jiang, Jianbo Wang
Summary: This study systematically investigates the effects of twin boundary orientation and spacing on the deformation mechanisms in nickel nanowires. The findings demonstrate that twin boundaries play distinct roles in the mechanical deformations of face-centered-cubic nanowires.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Yana Men, Xiaozhi Su, Peng Li, Yue Tan, Chuangxin Ge, Shuangfeng Jia, Lei Li, Jianbo Wang, Gongzhen Cheng, Lin Zhuang, Shengli Chen, Wei Luo
Summary: This study proposes a surface oxygen insertion strategy to tailor the electronic structures of Ni electrocatalysts, which increases the hydroxide binding energy and improves the performance of alkaline hydrogen oxidation reaction.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Yongfa Cheng, Yimei Xie, Zunyu Liu, Shuwen Yan, Yanan Ma, Yang Yue, Jianbo Wang, Yihua Gao, Luying Li
Summary: Among the increasingly popular miniature and flexible smart electronics, two-dimensional materials show great potential in the development of flexible electronics owing to their layered structures and outstanding electrical properties. MXenes have attracted much attention in flexible electronics owing to their excellent hydrophilicity and metallic conductivity. This study proposes a strategy for rapid gas foaming to construct interlayer tunable MXene aerogels, which can generate maximized electron channels under pressure for effective utilization of the surface metal properties of MXene. The resulting pressure sensor exhibits high sensitivity, fast response time, and good cycling stability, and has applications in various fields.
Article
Chemistry, Physical
Weiwei Meng, Feng Hong, Guoxujia Chen, Xiaoxi Guan, Peili Zhao, Shuangfeng Jia, He Zheng, Jianbo Wang
Summary: The stability and optoelectrical properties of In5S4 have been investigated through density functional theory calculation and experimental verification. The results show that In5S4 follows the valence electron counting rule and exhibits strong visible light absorption, indicating its potential application in optoelectronic devices.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Materials Science, Multidisciplinary
Ligong Zhao, Guoxujia Chen, He Zheng, Shuangfeng Jia, Kaixuan Li, Renhui Jiang, Lei Li, Ying Zhang, Huayu Peng, Peili Zhao, Ziyang Huang, Jianbo Wang
Summary: By conducting in situ tensile experiments, this study reveals the strong influence of size on twinning behaviors and twin boundary-dislocation interaction mechanisms in body-centered cubic iron nanowires. Above a critical diameter of approximately 2.5 nm, deformation twinning dominates plasticity instead of dislocation slip. Isosceles twin boundaries mediated by 1/12 < 111 > partial dislocations are consistently observed. Two distinct twin boundary-related deformation mechanisms, twin variant re-orientation and twin boundary cracking, are uncovered for nanowires with diameters below and above 17 nm, respectively. Molecular dynamics and statics simulations provide the underlying mechanisms for size-dependent plasticity, which have been overlooked in previous experimental investigations. These findings emphasize the importance of grain size in mediating deformation behaviors in iron and offer possible guidance for optimizing the mechanical performance of single-crystalline and poly-crystalline iron-based materials, such as steel.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Renhui Jiang, Pei Li, Xiaoxi Guan, He Zheng, Shuangfeng Jia, Ligong Zhao, Huaiyuan Wang, Shuangshuang Huang, Peili Zhao, Weiwei Meng, Jianbo Wang
Summary: Framework structured tungsten bronzes show potential as electrode materials in sodium-ion batteries. However, the structural instability induced by sodium ion migration poses concerns for battery performance and safety. This study presents real-time experimental evidence of phase transitions in framework structured Na0.36WO3.14, with the formation of Na+-rich (Na0.48WO3) or Na+-deficient (NaxWO3, x < 0.36) phases under different external voltages. The atomistic phase transition mechanisms associated with sodium ion migration are revealed, offering insights for the design of stable sodium-ion batteries.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Huayu Peng, Yuxuan Hou, Weiwei Meng, He Zheng, Ligong Zhao, Ying Zhang, Kaixuan Li, Peili Zhao, Ting Liu, Shuangfeng Jia, Jianbo Wang
Summary: Through atomistic electron microscopy observations, the size-dependent twinning mechanisms in refractory body-centered cubic molybdenum nanocrystals under tensile loading are revealed. Two distinct twinning mechanisms involving the nucleation of coherent and inclined twin boundaries are uncovered in nanocrystals with smaller and larger diameters, respectively. The effects of different types of twin boundaries on electrical conductivity are quantified, providing valuable insights for the design of next-generation flexible nanoelectronics.
Article
Nanoscience & Nanotechnology
Meng Qi, Ziyang Huang, He Zheng, Ligong Zhao, Renhui Jiang, Jiaheng Wang, Jie Hu, Guoxujia Chen, Shuangfeng Jia, Jianbo Wang
Summary: We synthesized high-crystallinity and uniform few-layer MoS2 through chemical vapor deposition, and found that bilayer MoS2 exhibits the best sensitivity for detecting NO2 at room temperature compared to monolayer and trilayer counterparts. This is attributed to the more negative adsorption energy of NO2 on bilayer MoS2, which facilitates charge transfer and enhances the electrical response of gas sensors. This work provides insights into the layer-dependent gas-sensing performance and serves as a reference for designing room-temperature gas sensors with low power consumption and reliable responsivity.
ACS APPLIED NANO MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Huayu Peng, Yuxuan Hou, He Zheng, Ligong Zhao, Ying Zhang, Weiwei Meng, Ting Liu, Peili Zhao, Shuangfeng Jia, Jianbo Wang
Summary: This study reports the anisotropic mechanical behaviors in nanoscale body-centered cubic (bcc) metals. It is found that bcc molybdenum nanocrystals exhibit poor ductility along the [110] direction but possess relatively better ductility along the [001] and [112] orientations. The deformation mechanisms, including crack nucleation and propagation, deformation twinning, and activation of multiple dislocation slips, are responsible for the different ductility in different orientations. Molecular dynamics simulations provide insights into the defect dynamics that correlate with experimental observations. These findings advance the understanding of orientation-dependent mechanical properties and guide the design of bcc metals with enhanced ductility.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Jiaheng Wang, Xiaoxi Guan, He Zheng, Ligong Zhao, Renhui Jiang, Peili Zhao, Ying Zhang, Jie Hu, Pei Li, Shuangfeng Jia, Jianbo Wang
Summary: This study reveals the size-dependent phase transition of sub-2 nm Ga2O3 nanowires using in situ transmission electron microscopy, providing crucial parameters for designing and constructing metal-oxide-semiconductor field-effect transistors.
Article
Chemistry, Multidisciplinary
Jie Hu, He Zheng, Lei Li, Guoxujia Chen, Kaixuan Li, Meng Qi, Ying Zhang, Peili Zhao, Weiwei Meng, Shuangfeng Jia, Jianbo Wang
Summary: CuOx/C catalysts are widely used for the selective catalytic reduction of NOx due to their exceptional low-temperature denitration activity. In this study, the atomic-scale reaction between CuO and C was investigated using a transmission electron microscope. Two reaction mechanisms were proposed based on the volume ratio between C and CuO, and the reduction pathway was interpreted by considering the diffusion of O vacancy. This atomic-scale exploration provides promising prospects for the design of industrial de-NOx catalysts in the future.
Article
Chemistry, Physical
Renhui Jiang, Pei Li, Xiaoxi Guan, He Zheng, Shuangfeng Jia, Ligong Zhao, Huaiyuan Wang, Shuangshuang Huang, Peili Zhao, Weiwei Meng, Jianbo Wang
Summary: Framework structured tungsten bronzes have great potential as electrode materials for sodium-ion batteries. However, the structural instability caused by sodium ion migration remains a concern for battery performance and safety. In this study, we provide real-time experimental evidence of phase transitions in Na0.36WO3.14 framework structured tungsten bronze through the application of different external voltages. The mechanisms of phase transition associated with sodium ion migration are also revealed through theoretical calculations. This work contributes to a better understanding of phase instability in sodium tungsten bronzes and provides insights for designing high-stability sodium-ion batteries.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
