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Switching CO_(2) Electroreduction Selectivity Between C_(1) and C_(2) Hydrocarbons on Cu Gas-Diffusion Electrodes

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Energy & Environmental Materials 2023年第2期6卷 17-25页

作者： Jianfang Zhang Zhengyuan Li Rui Cai Tianyu Zhang Shize Yang Lu Ma Yan Wang yucheng wu Jingjie wu School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China Department of Chemical and Environmental Engineering University of CincinnatiCincinnati OH 45221USA Eyring Materials Center Arizona State UniversityTempe AZ 85287USA National Synchrotron Light Source II Brookhaven National LaboratoryUpton NY 11971USA

Regulating the selectivity toward a target hydrocarbon product is still the focus of CO_(2)electroreduction.Here,we discover that the original surface Cu species in Cu gas-diffusion electrodes plays a more important role than the surface roughness,local pH,and facet in governing the selectivity toward C_(1)or C_(2)hydrocarbons.The selectivity toward C_(2)H_(4) progressively increases,while CH_(4) decreases steadily upon lowering the Cu oxidation species fraction.At a relatively low electrodeposition voltage of 1.5 V,the Cu gas-diffusion electrode with the highest Cu^(δ+)/Cu^(0)ratio favors the pathways of∗CO hydrogenation to form CH_(4) with maximum Faradaic efficiency of 65.4%and partial current density of 228 mA cm^(−2)at−0.83 V vs RHE.At 2.0 V,the Cu gas-diffusion electrode with the lowest Cu^(δ+)/Cu^(0)ratio prefers C-C coupling to form C_(2)+products with Faradaic efficiency topping 80.1%at−0.75 V vs RHE,where the Faradaic efficiency of C_(2)H_(4) accounts for 46.4%and the partial current density of C_(2)H_(4) achieves 279 mA cm^(−2).This work demonstrates that the selectivity from CH_(4) to C_(2)H_(4) is switchable by tuning surface Cu species composition of Cu gas-diffusion electrodes.

关键词： C_(2)H_(4) CH_(4) CO_(2)electroreduction electrodeposition switchable selectivity

Manufacturing of tungsten and tungsten composites for fusion application via different routes

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Tungsten 2019年第1期1卷 80-90页

作者： yucheng wu School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China National-Local Joint Engineering Research Centre of Nonferrous Metals and Processing Technology Hefei University of TechnologyHefei 230009China Key Laboratory of Interface Science and Engineering of New Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China

Tungsten is a refractory metal with the highest melting point of all metals,which is considered as a promising candidate material for plasma-facing materials in the future fusion reactor.However,tungsten faces several challenges from intrinsic embrittlement,irradiation embrittlement and recrystallization embrittlement during the operation of the fusion reactor.To satisfy the fusion engineering application,an advanced tungsten material with the fine grain and dense microstructure is required and developed.This paper briefly introduces the application background of the tungsten materials and mainly illus-trates a series of common techniques for manufacturing advance tungsten materials,such as powder preparation technologies,bulk densification techniques,continuous processing technologies and the coating and additive manufacturing technologies.Furthermore,the development prospects for manufacturing techniques of tungsten materials are also presented in the end.Considering the tungsten materials employed in the fusion engineering application,combining these scalable techniques of the wet-chemical method,pressureless sintering and continuous deformation processing techniques would be the possible research and development routes to realize the manufacture of the advanced tungsten materials.

关键词： Tungsten Future fusion reactor Mechanical alloying Wet-chemical method Deformation processing

Activated carbon coated palygorskite as adsorbent by activation and its adsorption for methylene blue

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Journal of Environmental Sciences 2015年第7期27卷 97-105页

作者： Xianlong Zhang Liping Cheng Xueping wu Yingzhao Tang yucheng wu School of Chemistry and Chemical Engineering Hefei University of Technology School of Materials Science and Engineering Hefei University of Technology

An activation process for developing the surface and porous structure of palygorskite/carbon（PG/C） nanocomposite using ZnC l2 as activating agent was investigated. The obtained activated PG/C was characterized by X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）, field-emission scanning electron microscopy（SEM）, and Brunauer-Emmett-Teller analysis（BET） techniques. The effects of activation conditions were examined,including activation temperature and impregnation ratio. With increased temperature and impregnation ratio, the collapse of the palygorskite crystal structure was found to accelerate and the carbon coated on the surface underwent further carbonization. XRD and SEM data confirmed that the palygorskite structure was destroyed and the carbon structure was developed during activation. The presence of the characteristic absorption peaks of C_C and C-H vibrations in the FTIR spectra suggested the occurrence of aromatization. The BET surface area improved by more than 11-fold（1201 m2/g for activated PG/C vs. 106 m2/g for PG/C） after activation, and the material appeared to be mainly microporous. The maximum adsorption capacity of methylene blue onto the activated PG/C reached 351 mg/g. The activated PG/C demonstrated better compressive strength than activated carbon without palygorskite clay.

关键词： Palygorskite/carbon Activation Adsorption Methylene blue Compressive strength

Anti-corrosion performance of Si-surface-alloying NdFeB magnets obtained with magnetron sputtering and thermal diffusion

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Journal of Rare Earths 2023年第8期41卷 1203-1210,I0003页

作者： Jin Tao Bang Liu Pengjie Zhang Guangqing Xu Jun Lv Jun Huang Jian Yan Wei Sun Bingshan Li Dongmei Wang yucheng wu School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China BGRIMM Technology Group Co. Ltd.Beijing 102600China National Engineering Research Center for Magnetic Materials Beijing 102600China Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Anhui Provincial International S&T Cooperation Base for Advanced Energy MaterialsHefei University of TechnologyHefei 230009China

Si alloying in the surface layer of NdFeB magnets was realized by thermal diffusion combined with magnetron sputtering.The surface composition,phase structure and morphology of NdFeB(S-Si)specimens were characterized by an X-ray diffractometer,an X-ray photoelectron spectrometer and a field emission scanning electron microscope,respectively.The corrosion resistance of bare NdFeB(S-Si)was analyzed by static full immersion corrosion test and electrochemical experiments.Effects of sputtering and thermal diffusion on the microstructure and corrosion resistance of the surface layer were studied.Results show that surface alloying layer can effectively improve the corrosion resistance of bare NdFeB with the optimized static total immersion corrosion test time in NdFeB(1S-Si)-800 of 36 h,which is much longer than that of the pristine NdFeB(less than 0.5 h).The E_(corr)of NdFeB(1S-Si)-800 positively shifts from-1.05 to-0.92 V,indicating that the corrosion tendency is obviously lower.The J_(corr)is1.45×10^(-6)A/cm^(2)which is 2 orders of magnitude lower than that of the pristine NdFeB(5.25×10^(-4)A/cm^(2)).The intergranular composite oxides existing in Nd-rich phase contribute to the enhancement of corrosion resistance of Si-surface-alloying NdFeB.

关键词： NdFeB magnets Si surface alloying Magnetron sputtering Thermal diffusion Corrosion resistance Rare earths

Rare earth passivation and corrosion resistance of zinc coated NdFeB magnets

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Journal of Rare Earths 2022年第2期40卷 302-308,I0005页

作者： Jing Chen Hongyi Yang Guangqing Xu Pengjie Zhang Jun Lv Wei Sun Bingshan Lidi Jun Huang Dongmei Wang Xia Shu yucheng wu School of Materials Science and Engineering.Hefei University of Technology Hefei 230009China China International S&T Cooperation Base for Advanced Energy and Environmental Materials Hefei University of TechnologyHefei 230009China Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Anhui Provincial International S&T Cooperation Base for Advanced Energy MaterialsHefei University of TechnologyHefei 230009China BGRIMM Technology Group Co. Ltd.Beijing 102600China National Engineering Research Center for Magnetic Materials Beijing 102600China

Rare earth passivation was conducted on Zn coated NdFeB magnets by chemical reaction to enhance the corrosion resistance performance.Morphologies,micro structures and compositions of different passivated coatings were studied by X-ray diffraction,field emission scanning electron microscopy,and X-ray photoelectron spectroscopy,respectively.The corrosion behavior was evaluated by electrochemical measurement and neutral salt spray test.The results show that the rare earth passivation can enhance the corrosion resistance of Zn coated NdFeB magnets.When the concentration of cerium nitrate is 5 g/L,the passivated specimens can achieve the longest NSS time of 360 h,which is 144 h longer than that of the pristine Zn/NdFeB magnets.The passivation layer on the Zn coating surface contributes to the enhancement of the magnets’corrosion resistance.

关键词： Sintered NdFeB magnets Rare earth passivation Zn coating Electroplating Corrosion resistance

Microstructure evolution and mechanical anisotropy of M50 steel ball bearing rings during multi-stage hot forging

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Chinese Journal of Aeronautics 2021年第11期34卷 254-266页

作者： Hongwei JIANG Yanran SONG yucheng wu Debin SHAN Yingying ZONG National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China AECC Harbin Bearing Co. LtdHarbin 150070China

This study aimed to explore the evolution of flow lines and microstructures of M50-steel bearing ring and the anisotropy of its tensile mechanical properties after Multi-Stage Hot Forging(MSHF) and subsequent spheroidizing annealing(MSHFA). To this end, the present study mainly employed stereo microscopy, Optical Metallurgical Microscopy(OMM), Scanning Electron Microscopy(SEM), and Electron Backscatter Diffraction(EBSD) to characterize and analyze the workpiece at each processing stage of MSHF while performing microhardness measurement and uniaxial tensile experiment to test and analyze the mechanical properties of the workpiece. Macro-structure observation showed that the simulation results of flow lines at each stage were consistent with the experimental results. Microscopic observation showed that, after MSHF, deformation gradually became less significant along the outward radial direction of the bearing ring. After MSHFA,the microstructures of the bearing ring became uniform, whereas primary carbides did not dissolve.The mechanical properties were better in the axial direction(AD) than in the radial(RD) and circumferential directions(CD) after MSHF due to the smaller grain width. After MSHFA, the mechanical properties in the ADs and CDs were better than those in the RDs, which was due to the large cross-sectional area of carbides along the flow-line direction.

关键词： Bearing ring Flow lines Forging Mechanical anisotropy Microstructure evolution

绿色信贷下电池厂及车企研发创新模式与策略研究

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运筹与管理 2024年第1期33卷 36-42页

作者：李江鑫栗继祖吴玉程太原理工大学经济管理学院山西太原030024 合肥工业大学国家先进能源与环境材料国际科技合作基地安徽合肥230009 太原理工大学教育部新材料界面科学与工程重点实验室山西太原030024

绿色信贷对研发投入、创新效应的促进作用受车企及电池厂研发模式与策略的影响。本文分别构建了车企与电池厂单一主导研发和双方独立研发模式下的供应链博弈模型,通过研发投入、创新效应的分析,对不同模式及策略进行了对比。结果表明:... 详细信息

绿色信贷对研发投入、创新效应的促进作用受车企及电池厂研发模式与策略的影响。本文分别构建了车企与电池厂单一主导研发和双方独立研发模式下的供应链博弈模型,通过研发投入、创新效应的分析,对不同模式及策略进行了对比。结果表明:不论是从社会效益还是创新效应看,电池厂主导的单一研发模式都不是最理想的策略,不能最大发挥绿色信贷的促进作用;绿色信贷下,合作对电池厂及车企研发投入的促进作用受电池成本比例、资金时间价值以及绿色信贷利率的影响;当单一方主导研发时,绿色信贷总能激励车企投入更大研发,而只有在合作状态下,才能提升电池厂的研发努力,而当双方独立研发时,绿色信贷下车企研发投入增加,而电池厂选择搭便车。

关键词：绿色信贷新能源汽车研发模式创新效应

Fungal defensins, an emerging source of anti-infective drugs

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Chinese Science Bulletin 2014年第10期59卷 931-935页

作者： yucheng wu Bin Gao Shunyi Zhu Group of Animal Innate Immunity State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences

With the rapid increase of antibiotic-resistant pathogens and the decline of discovery and development of new antibiotics,there is an urgent need to exploit alternative anti-infective drugs.Fungal defensin-like peptides are emerging as a class of new source of anti-infective drugs due to their potent antibacterial activity,low toxicity,and high serum stability.Fungal genome sequencing projects combined with the development of recombinant expression techniques will accelerate the discovery of fungal defensinlike peptides.

关键词： Antibiotic-resistance Micasin Fungus

Hf含量对湿化学法制备超细W-Y_(2)O_(3)复合材料显微组织与性能的影响

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中国有色金属学报 2024年第1期34卷 125-138页

作者：刘祯颜硕罗来马昝祥吴玉程合肥工业大学材料科学与工程学院合肥230009 合肥工业大学有色金属与加工技术国家地方联合工程研究中心合肥230009 合肥工业大学高性能铜合金材料及成形加工教育部工程研究中心合肥230009

本文在现有W-Y_(2)O_(3)材料基础上,引入微量Hf4+掺杂入Y_(2)O_(3),调节Y_(2)O_(3)与W晶粒之间的界面关系,从而改善W基材料的综合性能。通过改变Y与Hf元素的掺杂比例,获得纳米级W基复合粉体,在氢气气氛下常规烧结制备W-Y_(2)(Hf)O_(3)... 详细信息

本文在现有W-Y_(2)O_(3)材料基础上,引入微量Hf4+掺杂入Y_(2)O_(3),调节Y_(2)O_(3)与W晶粒之间的界面关系,从而改善W基材料的综合性能。通过改变Y与Hf元素的掺杂比例,获得纳米级W基复合粉体,在氢气气氛下常规烧结制备W-Y_(2)(Hf)O_(3)复合材料。采用SEM、TEM等表征手段对W-Y_(2)(Hf)O_(3)复合材料的性能进行表征分析,研究Y与Hf元素在材料中的作用规律。结果表明:掺杂Hf元素有利于后续氢气还原,在第二相掺杂量不变条件下,当Hf含量增加时,所获得的粉体粒径减小,W-3Y-7Hf的粒径约为100 nm,明显小于传统制备的W-Y_(2)O_(3)粉体。烧结后的块体晶粒尺寸细化,显微硬度和相对密度随之增大,成分为W-3Y-7Hf烧结块体显微硬度最高,为513.7HV_(0.2),致密度为97.6%。在钨基材料中同时添加Y与Hf元素会在钨晶粒的晶界与晶内处形成复合第二相氧化物Y_(2)Hf_(2)O_(7)颗粒,尺寸更小,弥散强化作用更强;其中,W-3Y-7Hf中第二相氧化物颗粒尺寸仅为200 nm左右,与钨晶界产生良好的界面结合关系,形成半共格界面。

关键词：纳米级钨基复合粉体湿化学法弥散强化复合第二相氧化物