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Surface modification of tungsten oxide by oxygen vacancies for hydrogen adsorption

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Journal of Materials Science & Technology 2022年第22期117卷 23-35页

作者： Q.Zhang f.W.Tang Z.zhao Z.R.Nie x.Y.Song faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing the adsorption process of hydrogen on surface of tungsten oxide was proposed based on the first-principle calculations. Multiple factors such as type of active surface, adsorption site and distribution of oxygen vacancies were considered to evaluate the hydrogen adsorption capability of tungsten oxide. The adsorption Gibbs free energies, electronic structures and bonding characteristics under various conditions were examined to reveal the influence of oxygen vacancies on the surface. It is found that the capability of hydrogen adsorption of tungsten oxide can be significantly enhanced by adjusting the oxygen vacancy on the outermost layer of certain active surfaces. The modeling predicts that the surface structure stability and gas adsorption ability of tungsten oxide can be simultaneously improved through the formation of W–H bonds. The proposed strategy for moderating surface provides a new approach to obtain excellent gas-sensitive metal oxide materials.

关键词： Metal oxide Gas-sensitive material Surface adsorption Oxygen vacancy first-principles calculation

fRICTION PROPERTIES Of OIL-INfILTRATED POROUS AAO fILM ON AN ALUMINUM SUBSTRATE

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 249-253页

作者： C.x.Jiang J.P.Tu S.Y.Guo M.f.fu x.B.zhao DepartmentofMaterialsScienceandEngineering ZhejiangUniversityHangzhou310027China／／DeparunentofMechanicalandElectronicEngineeringNanchangUniversityNanchang330029China DepartmentofMaterialsScienceandEngineering ZhejiangUniversityHangzhou310027China DepartmentofMechanicalEngineering ZhejiangInstituteofScienceandTechnologyHangzhou310012China DepartmentofMechanicalandElectronicEngineering NanchangUniversityNanchang330029China

The porous anodic aluminum oxide (AAO) film on a pure aluminum substrate was pre pared by a two-step anodization in a 0.3M oxalic acid solution and pore-enlargem ent treatment in the phosphoric acid aqueous solution at 50℃. The diameter of h ighly ordered pore on the AAO film was about 90nm, and the thickness of the AAO film was 3μm. The mineral oil was infiltrated in the ordered nanometer sized po res of AAO film on an aluminum substrate due to the capillarity effect. The fric tion coefficient was measured using a ball-on-disk tribotester. The tests were c onducted at loads range from 490 to 2450mN and at sliding velocities between 0.1 and 0.5m·s-1. Oil infiltration in porous AAO film modified friction and consid erably improved the wear resistance. As compared to the porous AAO film, the oil -infiltrated specimen had low friction coefficient. With increasing the applied load and sliding velocity, the friction coefficient of the oil-infiltrated film decreased. It indicates that the oil-infiltrated AAO film produced a new way to modify the friction and wear of aluminum alloy.

关键词： friction coefficient oil-infiltrated AAO film aluminum substrate

EffECTS Of HDDR PROCESS ON STRUCTURE AND MAGNETIC PROPERTIES Of Nd(fe,Ti)_(12)N_δ PREPARED BY MECHANICAL ALLOYING

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 68-78页

作者： B.ZCui x.K.Sun x.G.zhao W.Liu Q.f.xiao T.zhao Z.D.Zhang Y.C.Sui Chinese Acad of Sciences Shenyang China

The effects of the hydrogenation-disproportionation-desorption-recombination (HDDR) process on the structure and the magnetic properties of the mechanical alloying (MA) prepared Nd8fe84 Ti8 alloy and its nitride counterpart have been studied in detail. It has been found that Nd(fe, Ti)12Hδ is formed in the temperature range from 300 to 550°℃. The disproportionation is ready to start at 550°℃ and is complete at 960°℃.The desorption and the recombination are almost synchronized. The phase of Nd(fe,Ti)7 is formed at 750°℃ during the HDDR treatment. With increasing temperature of HDDR process, the metastable structure of TbCu7 type is gradually transformed into the structure of ThMn12 type. The intrinsic coercivity and the maximum magnetic energy product increase with increasing temperature of HDDR process.

关键词： Nd(fe Ti)_(12)N_δ compound,magnetic property hydrogenation

THE TYPE II DEfECT IN 18R MARTENSITE IN A Cu-Zn-Al ALLOY

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 29-32页

作者： J.x.Zhang Y.f.Zheng W.Cai L.C.zhao Harbin Inst of Technology Harbin China

Type H defect in 18R martensite in a Cu-Zn-Al alloy has been studied by high resolution electron microscopy. It was found that Type H defect is not fault internal to martensite plate; rather,it is a stack of plates A and C. The rare observation of Type H defect is considered to be due to the fact that thc slice is too thin to exist for self-accommodation.

关键词： shape memory alloy Cu-based alloy defect

Constructing Donor–Acceptor‑Linked COfs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu zhao Hang Ma Conghui Zhang Yongxin Yang Shuyuan Yu Haiye Zhu Yongjiang Sun Hong Guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China Yunnan Yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COfs)based on intramolecular charge transfer *** other reported COfbased solid-state electrolyte,the developed concept with D–A-linked COfs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity f-based ligand in COf electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LifePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor f atoms,which effectively expedites electron transferring from porphyrin to f-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery

ON THE A/D TYPE TWIN BOUNDARY IN 18R MARTENSITE Of A Cu-Zn-Al ALLOY

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Acta Metallurgica Sinica(English Letters) 1997年第5期10卷 425-429页

作者： Zhang, J.x. Zheng, Y.f. Cai, W. zhao, L.C. Harbin Inst of Technology Harbin China

The A/D type twin boundary in a Cu-Zn-Al shape memory alloy appears curved under TEM and shows irregularly serrated steps under HREM. Crystallographic analysis shows that the macroscopic curve results from non-self-accommodation of the boundary, the deviation from exact twin orientation and a preferential orientation for lower boundary energy.

关键词： Aluminum alloys Copper alloys Crystallography Electron microscopy Martensite Zinc alloys

Ozone concentrations, flux and potential effect on yield during wheat growth in the NorthwestShandong Plain of China

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Journal of Environmental Sciences 2015年第8期27卷 1-9页

作者： Zhilin Zhu xiaomin Sun fenghua zhao franz x.Meixner Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Biogeochemistry Department Max-Planck-Institute for Chemistry

Ozone（O3） concentration and flux（fo） were measured using the eddy covariance technique over a wheat field in the Northwest-Shandong Plain of China. The O3-induced wheat yield loss was estimated by utilizing O3exposure-response models. The results showed that：（1） During the growing season（7 March to 7 June, 2012）, the minimum（16.1 ppb V） and maximum（53.3 ppb V）mean O3 concentrations occurred at approximately 6：30 and 16：00, respectively. The mean and maximum of all measured O3 concentrations were 31.3 and 128.4 ppb V, respectively. The variation of O3 concentration was mainly affected by solar radiation and temperature.（2） The mean diurnal variation of deposition velocity（V d） can be divided into four phases, and the maximum occurred at noon（12：00）. Averaged V d during daytime（6：00–18：00） and nighttime（18：00–6：00） were 0.42 and 0.14 cm/sec, respectively. The maximum of measured V d was about1.5 cm/sec. The magnitude of V d was influenced by the wheat growing stage, and its variation was significantly correlated with both global radiation and friction velocity.（3） The maximum mean f o appeared at 14：00, and the maximum measured f o was-33.5 nmol/（m^2·sec）. Averaged f o during daytime and nighttime were-6.9 and-1.5 nmol/（m^2·sec）, respectively.（4） Using O3 exposure-response functions obtained from the USA, Europe, and China, the O3-induced wheat yield reduction in the district was estimated as 12.9% on average（5.5%–23.3%）. Large uncertainties were related to the statistical methods and environmental conditions involved in deriving the exposure-response functions.

关键词： Ozone concentration Ozone flux Deposition velocity Eddy covariance Yield loss estimation Cropland ecosystem

ExPERIMENTAL INVESTIGATION ON HISTORY-DEPENDENCEOf PLASTIC BEHAVIOR Of TYPE 302 STAINLESS STEELUNDER COMBINED AxIAL-TORSIONAL LOADS

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Acta Metallurgica Sinica(English Letters) 1997年第1期10卷 65-70页

作者： S.x. zhao x.f. Sun and Z.B. Kuang (Institute of Applied Mechanics, Southwestern Jiaotong University, Chengdu 610031, China)(Institute of Engineering Mechanics, xi’an Jiaotong University, xi’an 710049, China) Southwestern Jiaotong Univ Chengdu China

Experimental investigations were pedermed on the plastic deformation along bilinear strain paths with various values of corner-angle by subjecting thin-walled tubular specimens of type 302 stainless steel to combined axial and torsional loads. Variations of scalar and vectorial behavior of the stress response are discnssed in the vector space of plastic strain. It is found that the intrinsic geometry of loading path, the plastic strain history and the coapled effect among strain components effect effectively the stress response of the material. The experimental results also show that these effects will disappear gradually with increasing strain.

关键词： complex loading plastic delay angle history-dependence of plastic deformation

Strong coupling between a quasi-two-dimensional perovskite and a honeycomb plasmonic nanocone array

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Photonics Research 2025年第1期13卷 80-86页

作者： ZIxUAN SONG xUExUAN HUANG LINGYAO LI LEYI zhao JIAMIN xIAO JIAZHI YUAN ZHIHANG WANG CHENGHAO BI WENxIN WANG Qingdao Innovation and Development Center of Harbin Engineering University College of Physics and Optoelectronic Engineering Harbin Engineering University Department of Applied Physics The Hong Kong Polytechnic University

Recently organic-inorganic perovskite has been established as a promising platform for achieving room temperature exciton-polaritons, attributable to its superior optical coherence and robust exciton binding ***, when interfaced with metallic surfaces, the rapid degradation and quenching effect in perovskite have presented significant challenges, which critically hinders the exploration of light-matter interactions within metallic plasmonic structures. In this study, we report a quasi-two-dimensional lead halide perovskite that demonstrates a pronounced strong coupling phenomenon within an array of aluminum nanocones. The investigated quasi-two-dimensional perovskite structure exhibits high photoluminescence quantum efficiency and improved stability against metallic-induced degradation. Interestingly, the periodical arraying in honeycomb formation of plasmonic structure has advantages in angle-dependent dispersions and the loss neutralizing effectively. Besides,the plasmonic cone lattice characterized by its collective surface lattice resonance, features an exceptionally small mode volume and high quality, enhancing its interaction with the perovskite. A significant Rabi splitting of243 meV is observed at an incident angle of 30°. The dynamics of the Rabi oscillation is revealed by transient absorption spectra and theoretically analyzed by cavity quantum electrodynamics. This advancement in polariton research paves the way for novel applications, including quantum sources, enhanced photon-electron conversion efficiencies, and low-threshold lasing.

关键词： Cavity quantum electrodynamics Light matter interactions Optical constants Quantum efficiency Surface plasmon resonance Ti:sapphire lasers