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Calculation of Surface Excitation Parameters by a Monte Carlo Method

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Chinese Journal of Chemical Physics 2017年第1期30卷 83-89,I0002页

作者： Zhe Zheng Bo Da Shi-feng Mao ze-jun ding CAS Key Laboratory of Geospace Environment Department of Modern Physics University of Science and Technology of China Hefei 230026 China National Institute for Materials Science 1-2-1 Sengen Tsukuba Ibaraki 305-0047 Japan School of Nuclear Science and Technology University of Science and Technology of China Hefei 230026 China Hefei National Laboratory for Physical Sciences at the Microscale and Department of Physics University of Science and Technology of China Hefei 230026 China

Electron inelastic mean free path （IMFP） is an important parameter for surface chemical quantification by surface electron spectroscopy techniques. It can be obtained from analysis of elastic peak electron spectroscopy （EPES） spectra measured on samples and a Monte Carlo simulation method. To obtain IMFP parameters with high accuracy, the surface excitation effect on the measured EPES spectra has to be quantified as a surface excitation parameter （SEP）, which can be calculated via a dielectric response theory. However, such calculated SEP does not include influence of elastic scattering of electrons inside samples during their incidence and emission processes, which should not be neglected simply in determining IMFP by an EPES method. In this work a Monte Carlo simulation method is employed to determine surface excitation parameter by taking account of the elastic scattering effect. The simulated SEPs for different primary energies are found to be in good agreement with the experiments particularly for larger incident or emission angles above 60° where the elastic scattering effect plays a more important role than those in smaller incident or emission angles. Based on these new SEPs, the IMFP measurement by EPES technique can provide more accurate data.

关键词： Eelastic peak electron spectroscopy Surface excitation parameter Monte Carlo simulation

Simulation Study of Electron Beam Induced Surface Plasmon Excitation at Nanoparticles

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Chinese Journal of Chemical Physics 2018年第5期31卷 655-660,735页

作者： Zhe Zheng Bo Da Ke-jun Zhang ze-jun ding CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics Hefei National Laboratory for Physical Sciences at the Microscale and Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Geospace Environment Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei 230026China Center for Materials research by Information Integration(CMI2) Research and Services Division of Materials Data and Integrated System(MaDIS)National Institute for Materials Science1-2-1 SengenTsukubaIbaraki 305-0047Japan

Phenomenon of localized surface plasmon excitation at nanostructured materials has attracted much attention in recent decades for their wide applications in single molecule detection,surface-enhanced Raman spectroscopy and *** addition to the excitation by external light field,an electron beam can also induce the local surface plasmon ***,electron energy loss spectroscopy(EELS)technique has been increasingly employed in experiment to investigate the surface excitation characteristics of metallic ***,a present theoretical analysis tool for electromagnetic analysis based on the discrete dipole approximation(DDA)method can only treat the case of excitation by light *** this work we extend the DDA method for the calculation of EELS spectrum for arbitary nanostructured *** have simulated EELS spectra for different incident locations of an electron beam on a single silver nanoparticle,the simulated results agree with an experimental measurement very *** present method then provides a computation tool for study of the local surface plasmon excitation of metallic nanoparticles induced by an electron beam.

关键词： Surface plasmon excitation Nanostructured materials Nanoparticles Electron energy loss spectroscopy

Hierarchical Silver Indium Tungsten Oxide Mesocrystals with Morphology-, Pressure-, and Temperature-Dependent Luminescence Properties

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Nano Research 2010年第6期3卷 395-403页

作者： Bo Hu Li-Heng Wu Zhi Zhao Meng Zhang Shao-Feng Chen Shu-Juan Liu Hong-Yan Shi ze-jun ding Shu-Hong Yu Division of Nanomaterials and Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryDepartment of Materials Science and Engineeringthe National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China Division of Instruments Center for Physical Science Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Department of Physics Hefei National Laboratory for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China

Highly hierarchical structures of silver indium tungsten oxide(AgIn(WO_(4))_(2))mesocrystals can be rationally fabricated via the microwave-assisted synthesis method by tuning the initial concentrations of the *** spectra of hierarchical AgIn(WO_(4))_(2) mesocrystals were measured to investigate the correlation between the morphology,pressure,and temperature and their luminescence *** materials showed interesting white emission when excited by visible light of wavelength 460 ***(WO_(4))_(2) materials having different morphologies displayed notable differences in photogenerated emission *** emission was strongly correlated with the surface nanostructures of outgrowths,with larger amounts of outgrowths leading to stronger emission *** pressure-and temperature-dependent photoluminescence properties of these materials have also been investigated under hydrostatic pressures up to 16 GPa at room temperature and in the temperature range from 10 to 300 K.

关键词： Photoluminescence AgIn(WO_(4))_(2) mesocrystal morphology high-pressure temperature

超宽禁带半导体NaYO_(2)的光电性质的第性原理研究

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Chinese Journal of Chemical Physics 2023年第2期36卷 186-192,I0055页

作者： Nisar Muhammad M.U.Muzaffar 李会民丁泽军中国科学技术大学物理系合肥微尺度物质科学国家研究中心合肥230026 中国科学技术大学合肥微尺度物质科学国家研究中心国际功能材料量子设计中心中国科学院量子信息与量子物理卓越中心合肥230026 中国科学技术大学超级计算中心合肥230026

超宽禁带半导体在发展电子器件的性能方面具有巨大潜力.本文利用密度泛函理论和精确的屏蔽杂化泛函计算了两种不同相的NaYO_(2)的电子和光学性质.电子结构计算结果表明,NaYO_(2)的单斜相和三方相都表现为直接带隙,大小分别5.6 eV和5.4 ... 详细信息

超宽禁带半导体在发展电子器件的性能方面具有巨大潜力.本文利用密度泛函理论和精确的屏蔽杂化泛函计算了两种不同相的NaYO_(2)的电子和光学性质.电子结构计算结果表明,NaYO_(2)的单斜相和三方相都表现为直接带隙,大小分别5.6 eV和5.4 eV,超越了公认的金刚石和GaN半导体材料,为半导体行业提供了一个物理上现实的材料平台.研究了NaYO_(2)两相的光学性质,发现它们在红外和可见光区都是透明的.因此,NaYO_(2)可被用作红外窗口材料.

关键词： NaYO_(2) 第一性原理计算电子结构光学性质

From waste to wealth:Coal tar residue derived carbon materials as low-cost anodes for potassium-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 464-475页

作者： Zhonghua Lu jun Shen Xin Zhang Lingcong Chao Liang Chen ding Zhang Tao Wei Shoudong Xu College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China College of Chemistry Taiyuan University of TechnologyTaiyuan 030024China School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan 430205China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China

Carbon materials are widely recognized as highly promising electrode materials for various energy storage system *** tar residues(CTR),as a type of carbon-rich solid waste with high value-added utilization,are crucially important for the development of a more sustainable *** this study,we employed a straightforward direct carbonization method within the temperature range of 700-1000℃to convert the worthless solid waste CTR into economically valuable carbon materials as anodes for potassium-ion batteries(PIBs).The effect of carbonization temperature on the microstructure and the potassium ions storage properties of CTR-derived carbons(CTRCs)were systematically explored by structural and morphological characterization,alongside electrochemical performances *** on the co-regulation between the turbine layers,crystal structure,pore structure,functional groups,and electrical conductivity of CTR-derived carbon carbonized at 900℃(CTRC-900H),the electrode material with high reversible capacity of 265.6m Ah·g^(-1)at 50 m A·g^(-1),a desirable cycling stability with 93.8%capacity retention even after 100 cycles,and the remarkable rate performance for PIBs were ***,cyclic voltammetry(CV)at different scan rates and galvanostatic intermittent titration technique(GITT)have been employed to explore the potassium ions storage mechanism and electrochemical kinetics of *** indicate that the electrode behavior is predominantly governed by surface-induced capacitive processes,particularly under high current densities,with the potassium storage mechanism characterized by an“adsorption-weak intercalation”*** work highlights the potential of CTR-based carbon as a promising electrode material category suitable for high-performance PIBs electrodes,while also provides valuable insights into the new avenues for the high value-added utilization of CTR.

关键词： coal tar residue carbon materials anode potassium-ion batteries high value-added

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： jun Jiang Zhenjie Lu Yanwen ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang junwu Zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Lithium-sulfur batteries Staged dendrite suppression Shuttle effect Surface-negatively-charged nanodiamond

Enhanced post-combustion CO2 capture and direct air capture by plasma surface functionalization of graphene adsorbent

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Journal of Energy Chemistry 2025年第1期100卷 653-664页

作者： Rahul Navik Eryu Wang Xiao ding Huang Yunyi Yiyu Liu Jia Li Guangdong-Hong Kong Joint Laboratory for Carbon Neutrality Jiangmen Laboratory of Carbon and Science and Technology Guangzhou HKUST Fok Ying Tung Research Institute The Hong Kong University of Science and Technology (Guangzhou) Carbon Neutrality and Climate Change Thrust Society Hub The Hong Kong University of Science and Technology (Guangzhou) Stoddart Institute of Molecular Science Department of Chemistry Zhejiang University

Graphene has enormous potential to capture CO2due to its unique properties and ***,graphene-based adsorbents have drawbacks of lower CO2adsorption capacity and poor *** work demonstrates a one-step rapid and sustainable N2/H2plasma treatment process to prepare graphene-based sorbent material with enhanced CO2adsorption *** treatment directly enriches amine species,increases surface area,and improves textural *** CO2adsorption capacity increases from 1.6 to 3.3 mmol/g for capturing flue gas,and from 0.14 to 1.3 mmol/g for direct air capture （DAC）.Importantly,the electrothermal property of the plasma-modified aerogels has been significantly improved,resulting in faster heating rates and significantly reducing energy consumption compared to conventional external heating for regeneration of *** aerogels display improved selectivity of 42 and 87 after plasma modification for 5 and 10 min,*** plasma-treated aerogels display minimal loss between 17%and 19% in capacity after 40 adsorption/desorption cycles,rendering excellent *** N2/H2plasma treatment of adsorbent materials would lower energy expenses and prevent negative effects on the global economy caused by climate change.

关键词： Carbon neutrality CO 2 capture Climate change Plasma treatment Graphene aerogel

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基于KNN-SVM的混合气体检测方法研究

光谱学与光谱分析 2025年第1期45卷 117-124页

作者：孙超胡润泽吴中旭刘年松丁建军江汉大学智能制造学院湖北武汉430056 精细爆破国家重点实验室湖北武汉430056

当今混合气体检测的研究中,针对多组分气体数据进行分类预测的数学算法百花齐放,如何快速且准确的检测出气体的成分和浓度逐渐成为当今研究的热门。然而在一些研究中,气体数据特征难以捕捉和判断,泛化能力不足,对气体数据进行分类预测... 详细信息

当今混合气体检测的研究中,针对多组分气体数据进行分类预测的数学算法百花齐放,如何快速且准确的检测出气体的成分和浓度逐渐成为当今研究的热门。然而在一些研究中,气体数据特征难以捕捉和判断,泛化能力不足,对气体数据进行分类预测的精度和效率表现较差。为此,针对一些数据偏差和泛化误差无界的问题,提出了一种K最近邻-支持向量机(KNN-SVM)算法,对一些难以作出分类的模糊气体数据进行二次分类,采用KNN和SVM两种算法共同抉择,更加全面的捕捉数据特征,根据实验确定各自算法的权重比从而提高判别气体类别的准确率,两种算法的集成也能提高算法的效率,对于不同种类的气体也能有良好的适应性的稳定性。该实验气体组分由12 mg·L^(-1)的C_(2)H_(2)、NO_(2)、SF_(6),10 mg·L^(-1)的NO_(2)、SF_(6)和5 mg·L^(-1)的C_(2)H_(2)(背景气体皆为N_(2))以及两瓶纯N_(2)的气瓶组成;通过互相混合和与N_(2)配比制备出实验设定的气体浓度。实验过程通过单一气体的检测可分别对三种气体获得60组训练集,并通过这60组数据可进行线性拟合得到每种气体的拟合线,得到气体浓度与气体吸收峰值的关系,通过实验检测得到的三种气体拟合线,其中C_(2)H_(2)拟合线的调整后R^(2)为0.991,NO_(2)拟合线的调整后R^(2)为0.981,SF_(6)拟合线的调整后R^(2)为0.987,可得气体检测的准确性。再通过互相混合进行检测可分别获得40组训练集,采用KNN-SVM算法对混合气体进行分类和预测,后通过拟合线即可反演出混合气体中每种气体的浓度。将该算法与传统SVM算法进行各种分类指标对比均可显示出该算法的有效性和优越性。实验结果表明,KNN-SVM算法在气体分类预测方面表现出卓越的性能,准确率高达99.167%,AUC(area under curve)值达99.375%。这一算法不仅提高了气体检测的准确性,还增强了泛化能力可适应多样化的气体组分,为实时气体检测系统提供了有力支持。

关键词：光声光谱气体检测 KNN-SVM 分类预测

Breaking new ground in photocatalysis: lutetium texaphyrin as a trigger for pyroptosis through biomolecular photoredox reactions

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Science China Chemistry 2025年第1期 1-2页

作者： Qihang ding Mengrong He Meijia Gu Department of Chemistry Korea University Department of Ultrasound Medicine Union Hospital Tongji Medical College Huazhong University of Science and Technology Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (MOE) School of Pharmaceutical Sciences Wuhan University

Malignant neoplasms consistently pose a significant threat to global public health [1,2]. In recent years, immunotherapy has demonstrated remarkable clinical success; however, its efficacy is limited by the scarcity of immune cell infiltration within tumor microenvironments. Cell pyroptosis, a gasdermin-mediated process characterized by cellular swelling,rupture, and the release of intracellular contents such as IL-1β, IL-18, ATP, HMGB1, plays a crucial role in this context[3,4].

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