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Designing Electronic Structures of Multiscale Helical Converters for Tailored Ultrabroad Electromagnetic Absorption

Nano-Micro Letters 2025年第1期17卷 439-455页

作者： Zhaobo Feng Chongbo Liu Xin Li Guangsheng Luo Naixin Zhai Ruizhe Hu Jing Lin Jinbin Peng Yuhui Peng Renchao Che key laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle School of Environmental and Chemical EngineeringNanchang Hangkong UniversityNanchang 330063People’s Republic of China School of Physics and Materials Nanchang UniversityNanchang 330031People’s Republic of China key laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063People’s Republic of China laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People’s Republic of China

atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)***,the relationship between configuration and electromagnetic(EM)loss mechanism has remained ***,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA *** calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM *** a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 *** precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm ***,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB *** innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications.

关键词： Metal-nonmetal co-doping 3d-2p orbital coupling Spin polarization Helical structure Broadband EM wave absorption

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Improvements on the third generation of electron momentum spectrometer

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Chinese Physics B 2008年第5期17卷 1729-1737页

作者：宁传刚张书锋邓景康刘昆黄艳茹罗志弘 Department of Physics and key laboratory of atomic and molecular nanosciences of Ministry of Education Tsinghua University

The significant modifications to our recently constructed electron momentum spectrometer have been implemented. Compared with our previous report, the energy and the angle resolutions are significantly improved and reach △E = 0.45 eV, △θ = ±0.53° and △φ = ±0.84°, respectively. Moreover, the details of data reduction and the relation between azimuthal angle range and the sensitivity are discussed.

关键词： electron momentum spectrometer double toroidal analyser oxide cathode Monte Carlo simulation

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Unveiling the promotion role of ZnO on Zn-Al spinel oxide for CO2 hydrogenation

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Journal of Energy Chemistry 2025年第1期100卷 18-25页

作者： Tongyao Wang Xinlong Yao Lixin Liang Hongyu Chen Pan Gao Guangjin Hou State key laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The Zn-Al spinel oxide stands out as one of the most active catalysts for high-temperature methanol synthesis from CO2hydrogenation. However, the structure–activity relationship of the reaction remains poorly understood due to challenges in atomic-level structural characterizations and analysis of reaction intermediates. In this study, we prepared two Zn-Al spinel oxide catalysts via coprecipitation（ZnAl-C）and hydrothermal（ZnAl-H） methods, and conducted a comparative investigation in the CO2hydrogenation reaction. Surprisingly, under similar conditions, ZnAl-C exhibited significantly higher selectivity towards methanol and DME compared to ZnAl-H. Comprehensive characterizations using X-ray diffraction（XRD）, Raman spectroscopy and electron paramagnetic resonance（EPR） unveiled that ZnAl-C catalyst had abundant ZnO species on its surface, and the interaction between the ZnO species and its ZnAl spinel oxide matrix led to the formation of oxygen vacancies, which are crucial for CO2adsorption and activation. Additionally, state-of-the-art solid-state nuclear magnetic resonance（NMR） techniques,including ex-situ and in-situ NMR analyses, confirmed that the surface ZnO facilitates the formation of unique highly reactive interfacial formate species, which was readily hydrogenated to methanol and DME. These insights elucidate the promotion effects of ZnO on the ZnAl spinel oxide in regulating active sites and reactive intermediates for CO2-to-methanol hydrogenation reaction, which is further evidenced by the significant enhancement in methanol and DME selectivity observed upon loading ZnO onto the ZnAl-H catalyst. These molecular-level mechanism understandings reinforce the idea of optimizing the ZnO-ZnAl interface through tailored synthesis methods to achieve activity-selectivity balance.

关键词： Reaction intermediates

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Highest Occupied molecular Orbital of Cyclopentanone by Binary （e, 2e） Spectroscopy

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Chinese Physics Letters 2006年第3期23卷 583-586页

作者：张书锋宁传刚邓景康任雪光苏国林杨铁成黄艳茹 Department of Physics and key laboratory of atomic and molecular nanosciences of MOE Tsinghua University Beijing 100084

We report the first measurements of the momentum profiles of highest occupied molecular orbital （HOMO） and the complete valence shell binding energy spectra of cyclopentanone with impact energies of 600 and 1200 eV by a binary （e, 2e） spectrometer. The experimental momentum profiles of the HOMO orbital are compared with the theoretical momentum distribution calculated using the Hartree Fock and density functional theory methods with various basis sets. However, none of these calculations gives a completely satisfactory description of the momentum distributions of the HOMO 762. The inadequacy of the calculations could result in the intensity difference of the second maximum at p-1.2a.u. between the experiment and the theory. The discrepancy between experimental and theoretical data in the low-momentum region is explained with the distorted wave effect.

关键词： ELECTRON MOMENTUM SPECTROSCOPY SPECTROMETER HYDROGEN SPECTRA DENSITY

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Interpretation of the Experimental Electron Momentum Spectra of 5e1/2 and 5e3/2 Orbitals of CF3I with Relativistic Calculations

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Chinese Physics Letters 2010年第7期27卷 98-100页

作者：刘昆宁传刚邓景康 Department of Physics and key laboratory of atomic and molecular nanosciences of MOE Tsinghua University Beijing 100084

With our newly developed method, we calculate the spin-orbit splitting states 5e1/2 and 5e3/2 of the CF3I molecule incorporating the relativistic effects. Our theoretical results agree excellently with the recent experimental observations. The present study shows that relativistic effects can evidently change the electron momentum distributions of molecular orbitals when a medium Z element is included, such as iodine.

关键词： Electron Momentum Calculations

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Experimental and Theoretical Investigation of Valence Orbitals in 1,4-Dioxane by Electron momentum Spectroscopy

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Chinese Physics Letters 2006年第5期23卷 1157-1160页

作者：杨铁成宁传刚苏国林邓景康张书锋任雪光黄艳茹 Department of Physics and key laboratory of atomic and molecular nanosciences of MOE Tsinghua University Beijing 100084

The binding energy spectrum of all valence orbitals and the momentum distributions of highest occupied molecular orbital （HOMO： 8ag）, 7bu＋7ag, 4bu, 2bg ＋4ag and 2au in 1, 4-dioxane are investigated by electron momentum spectroscopy （EMS） with 600 eV impact energy. The experimental results are consistent with theoretical calcula- tions of C2h chair conformation using the Hartree-Fock method and density functional theory with 6-311＋＋G^＊＊ and AUG-CC-PVTZ basis sets.

关键词： E 2E SPECTROSCOPY X-RAY SCATTERING MOLECULES

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Refit Silver Nanostructures Using a Convergent Electron Beam

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Chinese Physics Letters 2007年第4期24卷 1007-1009页

作者：张建红 key laboratory of atomic and molecular nanosciences (Ministry of Education) Department of Physics Tsinghua University Beijing 100084

Using a superionic conductor AgI thin film and a direct current electric field, we synthesize silver nanowires in diameter of about lOOnm. In order to refit the prepared nanowires, the samples are irradiated by a convergent electron beam （200 k V） inside a transmission electron microscope to prepare new small silver nanostructures. The new nanostructures are investigated in situ by high-resolution transmission electron microscope. This electron- induced crystal growth method is useful for technical applications in fabrication of nanodevices.

关键词： SHAPE-CONTROLLED SYNTHESIS METAL NANOWIRES COPPER NANOWIRES THIN-FILM GROWTH FIELD SOFT

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Faithful quantum secure direct communication protocol against collective noise

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Chinese Physics B 2010年第11期19卷 78-83页

作者：杨静王川张茹 School of Science Beijing University of Posts and Telecommunications key laboratory for atomic and molecular nanosciences and Department of Physics Tsinghua University

An improved quantum secure direct communication （QSDC） protocol is proposed in this paper. Blocks of entangled photon pairs are transmitted in two steps in which secret messages are transmitted directly. The single logical qubits and unitary operations under decoherence free subspaces are presented and the generalized Bell states are constructed which are immune to the collective noise. Two steps of qubit transmission are used in this protocol to guarantee the security of communication. The security of the protocol against various attacks are discussed.

关键词： quantum secure direct communication collective noise

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A Scenario to Provide atomic Data for Fusion Research in the Stage of Precision Physics

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Plasma Science and Technology 2010年第3期12卷 335-340页

作者：李家明高翔程诚张小乐青波 Department of Physics Shanghai Jiao Tong University Department of Physics and key laboratory of atomic and molecular Nanoseiences of Chinese Education Ministry Tsinghua University Department of Physics and key laboratory of atomic and molecular nanosciences of Chinese Education Ministry Tsinghua University

In order to provide abundant atomic data for fusion research in the stage of precision physics, a scenario, being a combination of indispensable theoretical calculations and bench-mark experimental measurements, is proposed. Such abundant atomic data are compiled mainly by theoretical calculations. Accuracies of such abundant data （i.e., atomic energy levels and cor- responding cross sections） are ascertained only by a finite number of bench-mark experimental measurements based on analytical calculation of scattering matrices.

关键词： R-matrix type methods electron-ion collision full-relativistic calculations

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Rhodium Moessbauer Effect Generated by Bremsstrahlung Excitation

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Chinese Physics Letters 2005年第10期22卷 2530-2533页

作者：程曜夏冰刘以农靳清秀 Department of Engineering Physics Tsinghua University Beijing 100084 key laboratory of atomic and molecular nanosciences Tsinghua University Beijing 100084

A method for effectively generating long-lived Moessbauer photons and methods for proving the associated ;Moessbauer effects are reported. For the first time, we observed resonant propagation and resonant absorption of 40-keV Moessbauer photons emitted from ^103Rh through （γ, γ′） process excited by bremsstrahlung. This is a new efficient way to generate long-lived isomer （〉 1ms） for Moessbauer spectroscopy with sufficient brilliance. An abnormally large ratio of resonant absorption between horizontal and vertical directions indicates horizontal trapping- of Moessbauer photons and anisotropic Mbssbauer emission, which can be attributed to gravitational effect on the ^103Rh Moessbauer isomer with extremely narrow 10^-19eV linewidth.

关键词： Rhodium Moessbauer Effect

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