检索结果-内蒙古大学图书馆

Enhancing the Electrochemical Activity of 2D Materials Edges through Oriented Electric Fields

ACS Nano 2024年第30期18卷 19828-19835页

作者： Wang, Hao Chen, Ding-Rui Lin, You-Chen Lin, Po-Han Chang, Jui-Teng Muthu, Jeyavelan Hofmann, Mario Hsieh, Ya-Ping Institute of Atomic and Molecular Sciences Academia Sinica Taipei10617 Taiwan Department of Physics National Taiwan University Taipei10617 Taiwan International Graduate Program of Molecular Science and Technology National Taiwan University Taipei10617 Taiwan Molecular Science and Technology Program Taiwan International Graduate Program Academia Sinica Taipei10617 Taiwan Department of Low Dimensional Systems J. Heyrovský Institute of Physical Chemistry Prague18200 Czech Republic

The edges of 2D materials have emerged as promising electrochemical catalyst systems, yet their performance still lags behind that of noble metals. Here, we demonstrate the potential of oriented electric fields (OEFs) to enhance the electrochemical activity of 2D materials edges. By atomically engineering the edge of a fluorographene/graphene/MoS2 heterojunction nanoribbon, strong and localized OEFs were realized as confirmed by simulations and spatially resolved spectroscopy. The observed fringing OEF results in an enhancement of the heterogeneous charge transfer rate between the edge and the electrolyte by 2 orders of magnitude according to impedance spectroscopy. Ab initio calculations indicate a field-induced decrease in the reactant adsorption energy as the origin of this improvement. We apply the OEF-enhanced edge reactivity to hydrogen evolution reactions (HER) and observe a significantly enhanced electrochemical performance, as evidenced by a 30% decrease in Tafel slope and a 3-fold enhanced turnover frequency. Our findings demonstrate the potential of OEFs for tailoring the catalytic properties of 2D material edges toward future complex reactions. © 2024 The Authors. Published by American Chemical Society.

关键词： Electric fields

来源：评论

学校读者我要写书评

暂无评论

Correlations in interacting electron liquids: Many-body statistics and hyperuniformity

引用

Physical Review B 2024年第10期110卷 104201页

作者： Haina Wang Rhine Samajdar Salvatore Torquato Department of Chemistry Department of Physics Princeton Center for Theoretical Science Princeton Materials Institute Program in Applied and Computational Mathematics

Disordered hyperuniform many-body systems are exotic states of matter with novel optical, transport, and mechanical properties. These systems are characterized by an anomalous suppression of large-scale density fluctuations compared to ordinary liquids. The structure factor of disordered hyperuniform systems often obeys the scaling relation S(k)∼Bkα with B,α>0 in the limit k→0. Ground states of d-dimensional free fermionic gases, which are fundamental models for many metals and semiconductors, are key examples of quantum disordered hyperuniform states with important connections to random matrix theory. However, the effects of electron-electron interactions as well as the polarization of the electron liquid on hyperuniformity have not been explored thus far. In this paper, we systematically address these questions by deriving the analytical small-k behaviors (and, associated, α and B) of the total and spin-resolved structure factors of quasi-one-dimensional, two-dimensional, and three-dimensional electron liquids for varying polarizations and interaction parameters. We validate that these equilibrium disordered ground states are hyperuniform, as dictated by the fluctuation-compressibility relation. Interestingly, free fermions, partially polarized interacting fermions, and fully polarized interacting fermions are characterized by different values of the small-k scaling exponent α and coefficient B. In particular, partially polarized fermionic liquids exhibit a unique form of multihyperuniformity, in which the net configuration exhibits a stronger form of hyperuniformity (i.e., larger α) than each individual spin component. The detailed theoretical analysis of such small-k behaviors enables the construction of corresponding equilibrium classical systems under effective one- and two-body interactions that mimic the pair statistics of quantum electron liquids. Our paper thus reveals that highly unusual hyperuniform and multihyperuniform states can be achieved in simple

关键词： Electronic structure Quantum many-body systems Two-dimensional electron gas

来源：评论

学校读者我要写书评

暂无评论

Tungsten Nitride (W5N6): An Ultraresilient 2D Semimetal

引用

Nano Letters 2024年第1期24卷 67-73页

作者： Chin, Hao-Ting Wang, Deng-Chi Gulo, Desman Perdamaian Yao, Yu-Chi Yeh, Hao-Chen Muthu, Jeyavelan Chen, Ding-Rui Kao, Tzu-Chun Kalbáč, Martin Lin, Ping-Hui Cheng, Cheng-Maw Hofmann, Mario Liang, Chi-Te Liu, Hsiang-Lin Chuang, Feng-Chuan Hsieh, Ya-Ping Molecular Science and Technology Program Taiwan International Graduate Program Academia Sinica Taipei10617 Taiwan International Graduate Program of Molecular Science and Technology National Taiwan University Taipei10617 Taiwan Institute of Atomic and Molecular Sciences Academia Sinica Taipei10617 Taiwan Department of Physics National Sun Yat-Sen University Kaohsiung80424 Taiwan Department of Physics National Taiwan Normal University Taipei11677 Taiwan Department of Physics National Taiwan University Taipei10617 Taiwan Institute of Physics Academia Sinica Taipei115201 Taiwan International Graduate Program of Nano Science and Technology National Taiwan University Taipei10617 Taiwan Graduate Institute of Applied Physics National Taiwan University Taipei10617 Taiwan J. Heyrovský Institute of Physical Chemistry Czech Academy of Sciences Dolejškova 2155/3 Prague182 23 Czech Republic Hsinchu300092 Taiwan Physics Division National Center for Theoretical Sciences Taipei10617 Taiwan Center for Theoretical and Computational Physics National Sun Yat-sen University Kaohsiung80424 Taiwan

Two-dimensional transition metal nitrides offer intriguing possibilities for achieving novel electronic and mechanical functionality owing to their distinctive and tunable bonding characteristics compared to other 2D materials. We demonstrate here the enabling effects of strong bonding on the morphology and functionality of 2D tungsten nitrides. The employed bottom-up synthesis experienced a unique substrate stabilization effect beyond van-der-Waals epitaxy that favored W5N6 over lower metal nitrides. Comprehensive structural and electronic characterization reveals that monolayer W5N6 can be synthesized at large scale and shows semimetallic behavior with an intriguing indirect band structure. Moreover, the material exhibits exceptional resilience against mechanical damage and chemical reactions. Leveraging these electronic properties and robustness, we demonstrate the application of W5N6 as atomic-scale dry etch stops that allow the integration of high-performance 2D materials contacts. These findings highlight the potential of 2D transition metal nitrides for realizing advanced electronic devices and functional interfaces. © 2023 American Chemical Society

关键词： Tungsten compounds

来源：评论

学校读者我要写书评

暂无评论

Binuclear Macrocyclic Silver(I) Complex of a Bis(carbone) Pincer Ligand: Synthesis and Application as a Carbone-Transfer Agent

引用

Inorganic chemistry 2023年第32期62卷 12664-12673页

作者： Aweke, Bamlaku Semagne Yu, Cheng-Han Shen, Jiun-Shian Wang, Sheng Yap, Glenn P. A. Chen, Wen-Ching Ong, Tiow-Gan Institute of Chemistry Academia Sinica Taipei11529 Taiwan Department of Applied Chemistry National Yang Ming Chiao Tung University Hsinchu30010 Taiwan Department of Chemistry National Taiwan University Taipei106216 Taiwan Department of Medicinal and Applied Chemistry National Taiwan University 10617 Kaohsiung Medical University Kaohsiung80708 Taiwan Sustainable Chemical Science and Technology Taiwan International Graduate Program Academia Sinica Taipei11529 Taiwan Department of Chemistry and Biochemistry University of Delaware NewarkDE19716 United States

A facile synthesis of a binuclear AgI complex 2 of a bis(carbone) ligand L and its application as a carbone-transfer agent for the generation of other transition-metal complexes of AuI (3), NiII (4), and PdII (5) is presented. Complex 2 was synthesized through multiple synthetic routes under mild reaction conditions using the tetracationic [LH4][OTf·Cl]2 precursor salt, the dicationic [LH2][OTf]2 ylide salt, and the free ligand L. The first two synthesis routes require no prior isolation of the air-, moisture-, and temperature-sensitive free ligand L, thus affording complex 2 with high yield and purity. Multinuclear NMR techniques, high-resolution mass spectrometry, and single-crystal X-ray diffraction analysis confirmed the identity of complex 2 as a binuclear AgI complex of L with a molecular formula of [L2Ag2][OTf]2 and a 16-membered-ring metallomacrocyclic structure. During the transmetalation reaction with AuI, the binuclear nature of complex 2 remains intact to give analogous complex 3 ([L2Au2][OTf]2). However, the dimeric structure was disrupted upon the carbone-transfer reaction with NiII and PdII, yielding mononuclear C-N-C pincer-type complexes 4 ([LNiCl][OTf]) and 5 ([LPdCl][OTf]), respectively. These results demonstrated the versatile use of complex 2 as a carbone-transfer agent to other transition metals regardless of the type or size of the metals or the geometry they prefer. © 2023 American Chemical Society.

关键词： Transition metals

来源：评论

学校读者我要写书评

暂无评论

Structural,dielectric and magnetic properties of terbium doped strontium spinel ferrite(SrFe_(2)O_(4))synthesized by sol-gel method

引用

Journal of Rare Earths 2025年第2期43卷 337-344,I0004页

作者： Rifat Shaheen Hafeez Ullah M.M.Moharam Ahmad M.Saeedi Ebraheem Abdu Musad Saleh Muhammad Ijaz Adel A.El-Zahhar Gamil A.A.M.Al-Hazmi Sana Ullah Asif Hafiz Muhammad Tahir Institute of Physics Gomal UniversityDera Ismail Khan29220KPPakistan Department of Chemistry College of Arts and SciencesPrince Sattam Bin Abdulaziz UniversityWadi Al-Dawasir11991Saudi Arabia Chemical and Electrochemical Processing Department Central Metallurgical Research and Development Institute(CMRDI)PO.Box 87Helwan11421Egypt Department of Physics Faculty of Applied ScienceUmm AL-Qura UniversityMakkah24382Saudi Arabia Department of Chemistry College of ScienceKing Khalid UniversityP.0.Box 9004Abha61413Saudi Arabia School of Materials and Energy Yunnan UniversityKunming650091China Department of Physics Govt.Graduate College Taunsa Sharif32100Pakistan

In this research work,sol-gel technique was employed to prepare the strontium based spinel ferrite nanoparticles(SrFe_(2)O_(4))with different ratios of terbium(Tb).Different characterization techniques were used to investigate the structural,morphological,dielectric and magnetic properties of the prepared samples.X-ray diffraction(XRD)result suggests that face-centered cube spinel nanocrystalline structure is *** size of the SrFe_(2)O_(4)decreases with rising of Tb *** morphology,shape and size of the SrFe_(2)O_(4)were examined by scanning electron microscopy(SEM)analysis and results reveal inhomogeneous distributions of the nanostructures with high *** electrical resistivity of the SrFe_(2)O_(4)increases with rising of Tb ratio,which is confirmed from the cyclic *** is observed that dielectric constant of all the samples decreases with the increasing frequency *** is determined that the dielectric constants of the spinel ferrites are frequency dependent and decrease with increasing the frequency of applied electric *** magnetic behavior of SrFe_(2)O_(4)with different ratios of Tb was studied and it is found that the saturation magnetization values of samples decrease with increase in the substitution of Tb^(3+)at octahedral sites for Fe^(3+).This decrease in the values of M_(s) is also attributed to spin at surface of nanoparticles.

关键词： Sol-gel Structural properties Dielectric properties Magnetic properties Spinel ferrites Rare earths

来源：评论

学校读者我要写书评

暂无评论

Local order metrics for many-particle systems across length scales

引用

Physical Review Research 2024年第3期6卷 033262页

作者： Charles Emmett Maher Salvatore Torquato Department of Chemistry Department of Physics Princeton Institute for the Science and Technology of Materials Program in Applied and Computational Mathematics

Formulating order metrics that sensitively quantify the degree of order/disorder in many-particle systems in d-dimensional Euclidean space Rd across length scales is an outstanding challenge in physics, chemistry, and materials science. Since an infinite set of n-particle correlation functions is required to fully characterize a system, one must settle for a reduced set of structural information, in practice. We initiate a program to use the local number variance σN2(R) associated with a spherical sampling window of radius R (which encodes pair correlations) and an integral measure derived from it ΣN(Ri,Rj) that depends on two specified radial distances Ri and Rj. Across the first three space dimensions (d=1,2,3), we find these metrics can sensitively describe and categorize the degree of order/disorder of 41 different models of antihyperuniform, nonhyperuniform, disordered hyperuniform, and ordered hyperuniform many-particle systems at a specified length scale R. Using our local variance metrics, we demonstrate the importance of assessing order/disorder with respect to a specific value of R. These local order metrics could also aid in the inverse design of structures with prescribed length-scale-specific degrees of order/disorder that yield desired physical properties. In future work, it would be fruitful to explore the use of higher-order moments of the number of points within a spherical window of radius R [S. Torquato et al., Phys. Rev. X 11, 021028 (2021)] to devise even more sensitive order metrics.

关键词： Classical statistical mechanics

来源：评论

学校读者我要写书评

暂无评论

Real-space screening of quantum spin-Hall insulators

引用

Physical Review Materials 2024年第12期8卷 124203-124203页

作者： Alexander C. Tyner Pallab Goswami Graduate Program in Applied Physics Northwestern University Evanston Illinois 60208 USA Department of Physics and Astronomy Northwestern University Evanston Illinois 60208 USA

It was shown by Prodan in 2009 that both magnetic and nonmagnetic two-dimensional insulators can support quantized spin-Chern number in the absence of spin-rotation symmetry as a bulk topological invariant, which is robust against impurity effects. Recent studies on higher-order and fragile topological insulators further demonstrate that the spin-Chern number can exist without gapless edge states. Therefore, the presence of generalized quantum spin-Hall states in real materials can be difficult to identify using only symmetry-based indicators and Wannier obstruction. Such phases require more sophisticated probes of bulk topology. Magnetic flux tube has emerged as one such singular real-space probe that leads to spin-charge separation and allows for a precise diagnosis of the spin-Chern number. In this paper, we develop an automated workflow to scan the database of experimentally relevant, large band-gap, two-dimensional insulators using magnetic flux tubes. The results reveal many material candidates of higher-order topological insulators possessing double spin-Chern number, including the 1H-MX2 family of transition metal dichalcogenides. Our paper has broad implications for current efforts to employ these materials for new platforms of moiré systems.

关键词： Magnetic flux

来源：评论

学校读者我要写书评

暂无评论

Multifunctional resonant wavefront-shaping meta-optics based on multilayer and multi-perturbation nonlocal metasurfaces

引用

Light(Science & Applications) 2022年第9期11卷 2194-2206页

作者： STEPHANIE CMALEK ADAM COVERVIG ANDREA ALÙ NANFANG YU Department of Applied Physics and Applied Mathematics Columbia UniversityNew YorkNY 10027USA Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY 10031USA Physics Program Graduate CenterCity University of New YorkNew YorkNY 10016USA

Photonic devices rarely provide both elaborate spatial control and sharp spectral control over an incoming *** optical metasurfaces,for example,the localized modes of individual meta-units govern the wavefront shape over a broad bandwidth,while nonlocal lattice modes extended over many unit cells support high quality-factor ***,we experimentally demonstrate nonlocal dielectric metasurfaces in the near-infrared that offer both spatial and spectral control of light,realizing metalenses focusing light exclusively over a narrowband resonance while leaving off-resonant frequencies *** devices attain this functionality by supporting a quasi-bound state in the continuum encoded with a spatially varying geometric *** leverage this capability to experimentally realize a versatile platform for multispectral wavefront shaping where a stack of metasurfaces,each supporting multiple independently controlled quasi-bound states in the continuum,molds the optical wavefront distinctively at multiple wavelengths and yet stay transparent over the rest of the *** a platform is scalable to the visible for applications in augmented reality and transparent displays.

关键词： spectrum resonant supporting

来源：评论

学校读者我要写书评

暂无评论

Low-temperature spin Seebeck effect in nonmagnetic vanadium dioxide

引用

Physical Review B 2024年第2期110卷 024415-024415页

作者： Renjie Luo Tanner J. Legvold Liyang Chen Henry Navarro Ali C. Basaran Deshun Hong Changjiang Liu Anand Bhattacharya Ivan K. Schuller Douglas Natelson Department of Physics and Astronomy Applied Physics Graduate Program Rice Quantum Institute Department of Physics and Center for Advanced Nanoscience Materials Science Division Department of Electrical and Computer Engineering Department of Materials Science and NanoEngineering

The spin Seebeck effect (SSE) is sensitive to thermally driven magnetic excitations in magnetic insulators. Vanadium dioxide in its insulating low-temperature phase is expected to lack magnetic degrees of freedom, as vanadium atoms are thought to form singlets upon dimerization of the vanadium chains. Instead, we find a paramagnetic SSE response in VO2 films that grows as the temperature decreases below 50 K. The field and temperature-dependent SSE voltage is qualitatively consistent with a general model of paramagnetic SSE response and inconsistent with triplet spin transport. Quantitative estimates find a spin Seebeck coefficient comparable in magnitude to that observed in strongly magnetic materials. The microscopic nature of the magnetic excitations in VO2 requires further examination.

关键词： Spin Seebeck effect Paramagnets Strongly correlated systems

来源：评论

学校读者我要写书评

暂无评论

Terahertz phonon polariton concentrator based on perovskite oxides

Terahertz phonon polariton concentrator based on perovskite ...

引用

2023 Conference on Lasers and Electro-Optics, CLEO 2023

作者： Xu, Rui Lin, Tong Luo, Jiaming Chen, Xiaotong Blackert, Elizabeth R. Moon, Alyssa R. JeBailey, Khalil M. Zhu, Hanyu Department of Materials Science and Nano Engineering Rice University Houston United States Applied Physics Graduate Program Rice University Houston United States Program Rice University Houston United States

ISBN: (纸本)9781957171258

We report the experimental demonstration of surface phonon-polaritonic devices in a broad spectral range of 7-13 THz based on SrTiO3. We designed planar ultrafast concentrators that amplifies transient electric field by 6 times and measured an average field of 0.5 GV/m in an optically resolvable area in the far field. © 2023 The Author(s)

关键词： Perovskite

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：