Article
Materials Science, Multidisciplinary
Yizhong Guo, Jiao Teng, Guo Yang, Ang Li, Yao Deng, Chengpeng Yang, Lihua Wang, Xin Yan, Ze Zhang, Xiaoyan Li, En Ma, Xiaodong Han
Summary: Detailed monitoring of atomic-scale processes is crucial for understanding grain rotation in nanocrystalline metals. In this study, in situ atomic-resolution evidence reveals that the type of grain boundary plays a role in the atomic processes involved in grain rotation in nanocrystalline Pt. General GBs exhibit a combination of dislocation activities and atomic rearrangements, while tilt GBs mostly rely on dislocation activities. GB dislocation climb, glide, and reaction are often associated with Lomer-like dislocation formation and destruction.
Article
Chemistry, Multidisciplinary
Eric R. R. Hoglund, De-Liang Bao, Andrew O'Hara, Thomas W. W. Pfeifer, Md Shafkat Bin Hoque, Sara Makarem, James M. M. Howe, Sokrates T. T. Pantelides, Patrick E. E. Hopkins, Jordan A. A. Hachtel
Summary: Grain boundaries are a common microstructural feature that greatly influence the functionality of various materials. Extensive experimental and theoretical studies have been conducted to understand the correlation between atomic-scale grain boundary structures and macroscopic properties. In this study, a SrTiO3 grain boundary was examined using advanced microscopy and spectroscopy techniques, along with density functional theory. The results provide insights into the impact of individual boundaries on macroscopic properties through the analysis of localized grain boundary vibrations.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Wenjie Li, Weimin Li, Guo Chen, Liyun Wu, Jun Zhang, Ming Chen, Guohua Zhong, Junyi Zhu, Ye Feng, Hao Zeng, Chunlei Yang
Summary: Conducting atomic force microscopy is used to investigate the mechanism behind the lower power conversion efficiency (PCE) of CZTS solar cells compared to CIGS solar cells. The difference in efficiency is attributed to the distinct band alignment at the grain boundaries and grain interior for the two materials. CZTS demonstrates type-I band alignment, leading to enhanced carrier recombination and decreased PCE.
Article
Materials Science, Multidisciplinary
Zhengwu Fang, Boyang Li, Susheng Tan, Scott Mao, Guofeng Wang
Summary: This study reveals the atomic-scale migration behavior of a typical shear-coupled mixed tilt-twist GB (MGB) in Au nanocrystals. Two distinct migration patterns were observed, mediated by GB disconnections with different crystallographic parameters. The study also found that excess GB sliding and GB plane reorientation accommodate the GB migration. These findings provide valuable insights into optimizing the ductility of metallic nanocrystals through controlling GB migration.
Article
Chemistry, Multidisciplinary
Hui Zhang, Yue Yu, Xinyue Dai, Jinshan Yu, Hua Xu, Shanshan Wang, Feng Ding, Jin Zhang
Summary: By combining aberration-corrected scanning transmission electron microscopy and density functional theory calculations, this study investigated the fracture mechanics of 2D rhenium disulfide, revealing distinctive crack behaviors at different grain boundaries. The results show that grain boundaries aligned with Re chains are more prone to brittle intergranular fracture, while those not aligned with Re chains exhibit high resistance to fracture, impeding crack propagation. These findings provide new insights for material reinforcement and controllable cutting through grain boundary engineering.
Article
Geochemistry & Geophysics
Filippe Ferreira, Lars N. Hansen, Katharina Marquardt
Summary: The study focuses on the plastic deformation and the role of grain boundaries in olivine deformation. Specific types of grain boundaries created by dislocation activity facilitate grain-boundary sliding. With progressive deformation, there is an increase in abundance of apparently slip-transparent boundaries.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Materials Science, Multidisciplinary
Xiaojiang Long, Weihao Wang, Wanli Zhang, Guangzhao Wang, Wenxi Zhao
Summary: In this study, shock-induced sliding behavior of (0 0 1) twist grain boundaries in Cu bicrystal was investigated using molecular dynamics simulations. The sliding of grain boundaries is found to be produced by transverse particle motion in the constituent grains and is resisted by the viscosity of the grain boundaries. The magnitude of sliding is determined by the angle between the [1 0 0] direction in the grain and the shock direction.
RESULTS IN PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Snehanshu Pal, K. Vijay Reddy, Tingting Yu, Jianwei Xiao, Chuang Deng
Summary: The study reveals that in nanocrystalline Ni and Al models, the atomic excess volume and excess energy in grain boundaries exhibit a skew-normal distribution, and there is a weak inverse correlation between the two. The correlation between atomic excess volume and excess energy strongly depends on the type of grain boundary, indicating the absence of a universal trend between the two properties.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Qingkun Zhao, Qi Zhu, Zhenghao Zhang, Xiyao Li, Qishan Huang, Wei Yang, Jiangwei Wang, Huajian Gao, Haofei Zhou
Summary: This study proposes a machine learning-based framework for mapping atomic structure-stress using in situ transmission electron microscopy images. The study demonstrates that this framework can quantitatively map the atomic stress in different grain boundaries of crystalline metals, providing an important tool for studying atomic scale deformation behaviors and accelerating materials design.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Review
Chemistry, Multidisciplinary
Liu Yang, Yanyan Wang, Xu Wang, Shareen Shafique, Fei Zheng, Like Huang, Xiaohui Liu, Jing Zhang, Yuejin Zhu, Chuanxiao Xiao, Ziyang Hu
Summary: This review focuses on the application of atomic force microscopy (AFM)-based scanning probing techniques in investigating the local properties of polycrystalline photovoltaic materials. By studying the optoelectronic heterogeneities at grain interiors (GIs) and grain boundaries (GBs), it is possible to understand their critical roles in device performance and guide optimization. The potential of these AFM-based techniques in developing next-generation photovoltaics and optoelectronics is also discussed.
Article
Chemistry, Multidisciplinary
Pengcheng Jia, Liang Qin, Di Zhao, Yang Tang, Bo Song, Junhan Guo, Xiaomeng Li, Ling Li, Qiuhong Cui, Yufeng Hu, Zhidong Lou, Feng Teng, Yanbing Hou
Summary: The performance of perovskite solar cells is greatly influenced by the crystallization of the perovskite active layer, with neatly arranged crystal grains promoting less residual charge and improved device performance. The testing of residual charge at grain boundaries provides insight into carrier trap and detrap characteristics in photovoltaic devices.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Xiaopu Zhang, Mengyuan Wang, Hailong Wang, Moneesh Upmanyu, John J. Boland
Summary: By using scanning tunneling microscopy and calculations, we investigated the structure of emergent grain boundaries at the surfaces of planar nanocrystalline copper films. We found that there is a strong energetic preference for boundary cores to lie along close-packed planes, which leads to the restructuring of emergent grain boundaries at free surfaces. This new universal mechanism of boundary relaxation at metal surfaces is expected to have an important impact on grain coalescence, film stress evolution, and the properties of nanoscale materials.
Article
Nanoscience & Nanotechnology
Qian Liu, Leiming Fang, Zhengwei Xiong, Jia Yang, Ye Tan, Yi Liu, Youjun Zhang, Qing Tan, Chenchun Hao, Linhong Cao, Jun Li, Zhipeng Gao
Summary: The structure evolution of steels under different strain rates shows a strong rate effect, with dislocations forming low angle grain boundaries at high strain rates and low angle grain boundaries more likely to transform into high angle grain boundaries at low strain rates. The transformation from low angle grain boundaries to high angle grain boundaries is accompanied by grain rotation, and the texture of the steel changes accordingly. These results highlight the importance of the rate effect in guiding materials design and applications.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Chemistry, Multidisciplinary
Xinglong Ye, Fengkai Yan, Lukas Schaefer, Di Wang, Holger Gesswein, Wu Wang, Mohammed Reda Chellali, Leigh T. Stephenson, Konstantin Skokov, Oliver Gutfleisch, Dierk Raabe, Horst Hahn, Baptiste Gault, Robert Kruk
Summary: Hydrogen atoms play a critical role in permanent magnets, and engineering grain boundaries can achieve the giant magnetoelectric effect in these magnets.
ADVANCED MATERIALS
(2021)
Article
Multidisciplinary Sciences
Mei Wu, Xiaowei Zhang, Xiaomei Li, Ke Qu, Yuanwei Sun, Bo Han, Ruixue Zhu, Xiaoyue Gao, Jingmin Zhang, Kaihui Liu, Xuedong Bai, Xin-Zheng Li, Peng Gao
Summary: The study demonstrates the achievement of large strain gradients and atomic-scale flexoelectric polarization by exploiting the exotic structural inhomogeneity of grain boundaries, leading to a better understanding of the electrical activities of oxide ceramics and the alteration of electronic structures at grain boundaries. Additionally, the engineering of grain boundaries provides a general and feasible pathway to achieve tunable flexoelectricity in different materials.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Zhihua Zhai, Yan Wang, Conghui Si, Pan Liu, Wanfeng Yang, Guanhua Cheng, Zhonghua Zhang
Summary: A novel self-templating strategy was developed to synthesize one-dimensional nanoporous RhNi alloy nanowires. The RhNi nanowires exhibited excellent electrocatalytic activity and stability for hydrogen evolution reaction. This study provides a new solution for the preparation of highly active and stable electrocatalysts in clean energy systems.
Article
Chemistry, Multidisciplinary
Qiwen Zhang, Yixuan Hu, Haofei Wu, Xiaoran Zhao, Mingliang Wang, Sihong Wang, Ruohan Feng, Qing Chen, Fang Song, Mingwei Chen, Pan Liu
Summary: The article reports on a eutectic dealloying strategy to activate porous spinel NiFe2O4 nanowires with multivalent cation substitutions. The obtained NiFeXO4 exhibits superior electrocatalytic performance for the oxygen evolution reaction, delivering a benchmark current density and high stability. This is attributed to lattice distortion and electronic coupling, as well as the absorption of H2O molecules facilitated by the multication substitution strategy.
Article
Materials Science, Multidisciplinary
Yanying Li, Xiaocang Han, Zhen Lu, Lei Ying, Xinyao Wang, Yuqiao Zeng, Yi Gao, Qing Chen, Pan Liu
Summary: Understanding phase transitions and pore formation during vapor phase dealloying (VPD) is essential for optimizing the microstructure and composition of nanoporous metals. Using a gamma-CoZn precursor alloy, researchers found a two-step dealloying process and identified the formation of a microsized porous intermediate phase and subsequent growth of nanoporous alpha-Co. By investigating the atomic-scale mechanisms using advanced microscopy techniques, the researchers discovered the preferential formation of the intermediate phase on specific crystal planes and dominant diffusion of vacancies on the {110} planes of the precursor. The insights gained from this study can provide a new approach to fine-tuning the pore structure and composition of nanoporous metals.
Article
Chemistry, Multidisciplinary
Yanying Li, Qiwen Zhang, Xiaoran Zhao, Haofei Wu, Xinyao Wang, Yuqiao Zeng, Qing Chen, Mingwei Chen, Pan Liu
Summary: Low-cost and effective Co@CoO/RuO2 composites with tunable sizes and chemical compositions were fabricated by vapor phase dealloying. The composite catalyst exhibited superior OER activity, fast reaction kinetics, and long-term stability.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Shufen Chu, Junnan Jiang, Xiaoran Zhao, Baode Sun, Pan Liu
Summary: In this study, atomic scale visualizations of low-angle grain boundaries in nanoporous metal ligaments were conducted through in situ tensile straining inside a transmission electron microscope. The simultaneous climb and glide of grain boundary dislocations were observed and the motion paths of dislocation cores were precisely determined by real-time tracking.
Article
Materials Science, Multidisciplinary
Shuai Chen, Zachary H. Aitken, Subrahmanyam Pattamatta, Zhaoxuan Wu, Zhi Gen Yu, David J. Srolovitz, Peter K. Liaw, Yong-Wei Zhang
Summary: By employing density-functional theory calculations, Monte Carlo method, and molecular dynamic simulation, this study investigates the role of short-range ordering (SRO) on dislocation kinetics in a BCC MoTaTiWZr high-entropy alloy. The results demonstrate that SRO enhances the energy barriers for both edge and screw dislocation motion, giving rise to the dominance of edge dislocations in the BCC RHEA.
Article
Chemistry, Physical
Qiwen Zhang, Haofei Wu, Senhe Huang, Xiaoran Zhao, Chen Hou, Xiaodong Zhuang, Mingliang Wang, Jiuhui Han, Qing Chen, Pan Liu
Summary: Developing cost-effective, active, and robust oxygen evolution reaction (OER) electrocatalysts in alkaline electrolytes is crucial for the efficient conversion of renewable energy resources. In this study, 3D bicontinuous Mo-doped nanoporous NiFe oxide nanowires exhibited an efficient electro-catalytic OER performance. The catalyst demonstrated exceptional activity with a low overpotential and a small Tafel slope, outperforming most of the benchmark materials.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Xuyan Zhou, Shufen Chu, Zeyu Jin, Kailong Hu, Pan Liu, Hua-Jun Qiu, Xi Lin
Summary: Modifying the structures of metal-N-C single-atom catalysts to enhance their catalytic activities is challenging but desirable. The introduction of Ru to create RuFe-N-C or RuCo-N-C double-atom catalysts (DACs) can significantly improve the bifunctional ORR/OER activities, surpassing the individual Fe(Co)-N-C and Ru-N-C. The synergistic effect in RuM-N-C DACs is attributed to the combined optimized metal atoms, which alter the charge density and d-band center, affecting the adsorption energies and catalytic activity of intermediates. The synthesis of RuFe-N-C using a bimetal MOF precursor demonstrates exceptional ORR/OER activities, outperforming Fe-N-C, Ru-N-C, and even commercial Pt/C-RuO2.
ACS MATERIALS LETTERS
(2023)
Article
Engineering, Environmental
Dechao Chen, Jiao Lan, Feng Xie, Jin Peng, Ming Peng, Chen Sun, Zengxi Wei, Shuangliang Zhao, Mengjia Wang, Pan Liu, Lili Han, Yongwen Tan
Summary: Researchers have prepared a nanoporous Ru-doped ReSe2 catalyst with controllable selenium vacancies by regulating the amount of Ru dopants. The catalyst exhibits excellent performance in the N2 reduction reaction, with high Faradaic efficiency and NH3 yield rate. The study also provides insights into the synergistic effect of Ru dopants and selenium vacancies on regulating the proton coverage on the ReSe2 surface and enhancing the overall catalytic performance.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Mechanical
Tongqi Wen, Anwen Liu, Rui Wang, Linfeng Zhang, Jian Han, Han Wang, David J. Srolovitz, Zhaoxuan Wu
Summary: This study determines the properties of dislocation cores, twins, and cracks in HCP and BCC Ti using Deep Potential (DP), DFT, and linear elastic fracture mechanics. It provides insights into the behavior of slip dislocations and the brittleness of cracks on basal planes, as well as the energy and structure of twin boundaries. The results offer a comprehensive understanding of Ti plasticity and fracture.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Materials Science, Multidisciplinary
Jing Feng, Yanfeng Han, Xiaocang Han, Xiaodong Wang, Shuangxi Song, Baode Sun, Mingwei Chen, Pan Liu
Summary: Titanium diboride (TiB2) is an effective grain refiner for Al alloys, but the atomic kinetics of heterogeneous nucleation of Al on TiB2 are still unknown. In this study, atomic-scale observations were made to investigate the heterogeneous nucleation and growth kinetics of Al on self-formed TiB2 particles. It was found that an ordered Al monolayer forms on the Ti-terminated {0001}(TiB2) surface, and then an island-shaped Al nucleus with {111} stacking is initiated without a Ti-rich buffer layer. The interfacial lattice mismatch causes significant out-of-plane strain, which gradually decreases as the Al nucleus grows in layers. TiB2 particles stabilize the Al nuclei rather than promoting their free growth into grains when the experimental undercooling is below a certain threshold. These findings provide insights into the atomic-scale mechanisms of heterogeneous nucleation and growth of Al with the participation of TiB2 and the strain-dependent growth kinetics of Al nuclei.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Jing Feng, Xiaocang Han, Yanfeng Han, Xiaodong Wang, Shuangxi Song, Baode Sun, Mingwei Chen, Pan Liu
Summary: The interfacial lattice mismatch and local elastic strains in Al/TiB2 heterostructures were quantitatively studied using aberration-corrected transmission electron microscopy. In-plane atomic expansion and out-of-plane compression of Al layers on (0001)TiB2 were observed, promoting the extension of deformed Al layers for successful heterogeneous nucleation. These lattice strains could persist up to several Al atomic layers from the topmost (0001) surface of TiB2. Based on the compressive and expansive elastic strain relation, the Poisson's ratio in Al nuclei was estimated, and it was found that large mismatch strains caused abnormal changes in the Poisson's ratio. This study reveals the effect of lattice mismatch on the heterogeneous nucleation of Al on TiB2 and may have important implications in understanding the heterogeneous nucleation of Al.
SCRIPTA MATERIALIA
(2023)
Article
Multidisciplinary Sciences
Shuai Chen, Ping Liu, Qingxiang Pei, Zhi Gen Yu, Zachary H. Aitken, Wanghui Li, Zhaoxuan Wu, Rajarshi Banerjee, David J. Srolovitz, Peter K. Liaw, Yong-Wei Zhang
Summary: This study constructs nanolamellar high-entropy alloys and explores their mechanical properties using molecular dynamic simulation and density functional theory calculation. The results show that the nanolamellar structure exhibits ideal plastic behavior and remarkable shape memory effect, highlighting the importance of nanolamellar structures in controlling the mechanical and functional properties of high-entropy alloys.
Article
Nanoscience & Nanotechnology
Q. X. Guo, Z. C. Zheng, L. H. Wang, K. Wang, X. M. Wang, S. Cheng, W. He, G. H. Yu, H. -W. Lee, Y. Q. Guo, J. Teng, T. Zhu
Summary: We demonstrate spin-orbit torque induced perpendicular magnetization switching in a W/CoFeB/Zr/MgO multilayer that has been annealed. As the annealing temperature increases, the absolute damping-like efficiency remains constant. By converting the tungsten structure, the absolute spin Hall conductance can be increased. These results are important for the practical application of tungsten in SOT-based spintronics devices with high thermal stability and SOT efficiency.
