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Mesoporous CeO_(2)-C hybrid spheres as efficient support for platinum nanoparticles towards methanol electrocatalytic oxidation

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Journal of Rare Earths 2021年第6期39卷 674-681,I0003页

作者： weili li Qi Wang Lei Wang Xian-Zhu Fu Jing-li Luo College of Materials Science and Engineering Shenzhen UniversityShenzhen 518060China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Department of Chemical and Materials Engineering University of AlbertaEdmontonAlbenaT6G 2G6Canada

The development of direct methanol fuel cells(DMFCs) is partially limited by the poor kinetics of methanol oxidation reaction(MOR) at the anode *** was reported that the interaction between Pt and CeO_(2) enhances the electrocatalytic performance of Pt catalyst for *** this work,a hybrid material(CeO_(2)-C) composed of CeO_(2) and carbon was successfully prepared by a simple hydrothermal method followed by calcination in inert *** hierarchically porous nanostructure and especially good electronic conductivity of CeO_(2)-C make it an excellent support for Pt particles for application in electrocatalytic *** investigation reveals that triple-phase interface of Pt,carbon and CeO_(2) forms in Pt/CeO_(2)-C *** of the as-prepared catalyst for MOR was studied in alkaline *** Pt/CeO_(2)-C catalyst shows superior catalytic performance for MOR compared with Pt/CeO_(2) and the physical mixture of Pt/CeO_(2) and acetylene black(Pt/CeO_(2)+C).The significantly improved performance can be attributed to the synergetic effect between Pt particles and CeO_(2)-C support,and the better conductivity of CeO_(2)-*** study provides a possible method to expand the application potential of CeO_(2) materials in MOR,and may also be used in other electrocatalytic process.

关键词： Pt based catalyst Mesoporous CeO_(2)-C spheres Metal-support interaction Methanol oxidation Rare earths

Study of a Novel Fourth-generation Supported Ziegler-Natta Catalyst for Propylene Polymerization: Relationship between Catalyst Structure and Polymerization Properties

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China Petroleum Processing & Petrochemical Technology 2015年第1期17卷 39-47页

作者： liu Tao li weili Xia Xianzhi Mao Bingquan College of Materials Science and Engineering Beijing University of Chemical Technology National Engineering Research Center for Polyolefins Sinopec Beijing Research Institute of Chemical Industry

This article presents a detailed structural study of a new spherical Mg Cl2-supported Ti Cl4 Ziegler-Natta catalyst for isotactic propylene polymerization, and researches on the relationship between catalyst structure and polymer properties. The spherical support with the chemical composition of CH3CH2 OMg OCH(CH2Cl)2 has been synthesized from a new dispersion system and is used as the supporting material to prepare Ziegler-Natta catalyst. The XRD analysis indicates that the catalyst is fully activated with δ-Mg Cl2 in the active catalyst. The far-IR spectrometric results confirm again the presence of δ-Mg Cl2 in the active catalyst. Textural property of the active catalyst exhibits high surface area coupled with high porosity. The high activity in propylene polymerization is mainly ascribed to the full activation and the porous structure of the catalyst. Scanning electron microscopy/energy dispersive spectrometer mapping results indicate a uniform titanium distribution throughout the catalyst particles. Particle size analysis shows that the catalyst has a narrow particle size distribution. The perfect spherical shape, uniform titanium distribution and narrow particle size distribution of the catalyst confirm the advantage of polymer particles production with less fines. The solid state 13 C NMR and mid-IR spectroscopic analyses indicate that there exists strong complexation between diisobutyl phthalate and Mg Cl2, which leads to the high isotacticity of polypropylene.

关键词： Ziegler-Natta catalyst MgCl2 propylene polymerization structure characterization polymerization properties

Thermal analysis of high speed permanent magnetic generator

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Science China(Technological Sciences) 2012年第5期55卷 1419-1426页

作者： li weili ZHANG XiaoChen CHENG ShuKang CAO JunCi ZHANG YiHuang School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001China

High-speed permanent magnetic generators (HSPMG) are common and important power generation equipments used in distributed generation systems. A 100 kW level HSPMG is investigated in this paper, and it is fluid-thermal coupling analyzed. The transient 2D electromagnetic field while machine is under rated operating is analyzed by using the time-stepping FEM, from which the electromagnetic performances and the loss distributions are obtained. Then, an analysis model for fluid-solid temperature field analysis is established. Taking losses as the distributed heat sources, the 3D thermal field is coupling calculated. The variations of heat transfer coefficient and temperature of fluid in stator grooves along the axial direction, as well as the whole region 3D temperature distribution in HSPMG are obtained. Then, considering the variations of heat sources distributions and heat transfer conditions, 3D temperature fields of HSPMG operating under different speeds are calculated, and the influences of machine operating speed on the HSPMG thermal performance are studied, based on which, the functions of machine temperature with operating speed and stator windings resistance are proposed. The obtained conclusions may provide a useful reference for the design and research of HSPMG.

关键词： high-speed permanent magnetic generator electromagnetic fluid temperature speed

Enhanced efficiency and stability of perovskite solar cells by 2D perovskite vapor-assisted interface optimization

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Journal of Energy Chemistry 2020年第6期29卷 103-109,I0005页

作者： Minghui Chen Pengwei li Chao liang Hao Gu Weishuang Tong Shiping Cheng weili li Ganqing Zhao Guosheng Shao School of Chemistry and Environment Engineering Pingdingshan UniversityPingdingshan 467000HenanChina State Centre for International Cooperation on Designer Low-Carbon and Environmental Material(SCICDLCEM) School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001HenanChina

Organic–inorganic perovskites solar cells(PSCs)have attracted great attention due to their rapid progress in power conversion efficiency(PCE).However,there is still an enormous challenge to achieve both high efficiency and stability devices as the decomposition of perovskite materials under humid and light ***,we demonstrate that high efficiency and stability of PSCs can be obtained by the reaction of three-dimensional(3D)perovskite with 1,4-butanediamine iodide(BEAI2)*** incorporation of BEAI2 intensively promotes the crystallization of perovskite film with large grain size(~500 nm).Further characterization reveals that the post-treatment perovskite film delivered low interface trap density with long carrier lifetime(>200 ns),long carrier diffusion length(>600 nm)and large carrier mobility(>1.5 cm^2 V-1S-1).Solar cells employing such post-treatment films demonstrated 19.58%PCE without ***,the post-treatment devices can retain over 90%original efficiencies stored under ambient atmospheric conditions and exhibit better stability under 85℃and continuous illumination as a two-dimensional(2D)perovskite thin layer is formed on the surface/or at the grain boundaries of 3D *** study offers an effective way to obtain PSCs with high efficiency and stability.

关键词： Perovskite solar cells 2D/3D perovskite Post-treatment Carrier diffusion length Mobility

Hole-pinned defect-dipoles induced colossal permittivity in Bi doped SrTiO3 ceramics with Sr deficiency

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Journal of Materials Science & Technology 2020年第9期44卷 54-61页

作者： Yulong Qiao weili li Yulei Zhang Lu Jing Chang Gao Wenping Cao Dan Xu Weidong Fei School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China National Key Laboratory of Science and Technology on Precision Heat Processing of Metals Harbin Institute of TechnologyHarbin150001China School of light Industry Harbin University of CommerceHarbin150028China Key Laboratory of Quantum Manipulation&Control of Heilongjiang Province Harbin University of Science and TechnologyHarbin150080China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin150001China

Bi doped SrTiO3 ceramics with Sr deficiency,***1-1.5xBixTiO3(x=0,0.01,0.05,0.1),were prepared via conventional solid-state reaction route.A colossal permittivity(CP)over 104 with low dielectric loss less than 0.05wasobtained in x=0.05 Sr1-1.5xBixTiO3 *** addition,the dielectric constant is maintained at a value greater than 104 in the range of 102-105 Hz and almost frequency *** structure analysis and density functional theory calculations suggest that the Bi·Sr-V"Sr-Bi·Sr defect complex with hole-pinned defect-dipoles maybe responsible for the high-performance CP *** work gives a new way to achieve high performance CP materials in ABO3 perovskite ceramics.

关键词： Bi doped SrTiO3 Sr deficiency Colossal permittivity Low dielectric loss

Large linear electrostrain of acceptor-donor Co-doped ZnO films

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Journal of Materials Science & Technology 2022年第14期109卷 12-19页

作者： Chang Gao Yu Zhao weili li Yulong Qiao Zhao Wang Lu Jing Jie Sheng Wei-Dong Fei School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Science and Technology on Precision Heat Processing of Metals Harbin Institute of TechnologyHarbin 150001China Laboratory for Space Environment and Physical Science Research Center of Basic Space ScienceHarbin Institute of TechnologyHarbin 150001China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

In this paper we present the effective strategy of Fe^(3+)and li^(+)co-doping to enhance the electrostrain of ZnO thin ***_(0.88)(Fe_(0.06)li_(0.06))O thin film exhibits an excellent d_(33)^(*)value of 415 pm/V and large linear electrostrain of 0.68%after thermal-electric *** the X-ray diffraction and first principle calculation results have indicated that the Fe^(3+)and li^(+)ions are inclined to adopt a preferential alignment along the edges approximately parallel to[001]direction in the zinc-oxygen tetrahedron and constitute a defect dipole(ionic pairs).It is considered that the local lattice distortion and the electric field-triggered polarization extension and rotation generated by preferential distributed Fe^(3+)-li^(+)ionic pairs are responsible for the outstanding piezoelectric properties and large linear electrostrain.

关键词： Zno Piezoelectric Donor-acceptor ionic pairs Local lattice distortion Lead-free

Synthesis and electrochemical properties of a series of novel tetra(4-benzoyl)phenoxyphthalocyanine derivatives

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Science China Chemistry 2012年第9期55卷 1872-1880页

作者： WANG Kun FU Qiang MA JiCheng li weili LlWenJu HOU Yang CHEN lili ZHAO BaoZhong Faculty of Chemistry Northeast Normal UniversityChangchun 130024China

A novel phthalocyanine, 2,9（10）,16（17）,23（24）-tetra（4-benzoyl）phenoxyphthalocyanine, and its complexes with Zn（Ⅱ）, Cu（Ⅱ）, Co（Ⅱ）, and Ni（Ⅱ） have been synthesized and characterized by a combination of elemental analysis, IR, IH NMR, UV-vis spectroscopy and mass spectrometry. All of the materials are very soluble in common organic solvents such as dichloro- methane, chloroform, tetrahydrofuran, N,N-dimethylformamide and dimethyl sulfoxide. The Q band wavelengths of the com- plexes decrease in the order： Zn 〉 Cu 〉 Ni 〉 Co. Redox processes were observed at -1.06, -0.74, 0.51 and 0.98 V for the free phthalocyanine, at -0.72 and 1.04 V for the Co（Ⅱ） complex, at -1.24, -0.77, -0.24, 0.61 and 0,91 V for the Cu（Ⅱ） complex, and at -0.74 and 1.20 V for the Ni（Ⅱ） complex. The cyclic voltammograms of the phthalocyanine ring of the four species are similar, with reduction and oxidation couples each involving a one-electron transfer process.

关键词： synthesis electrochemical (4-benzoyl)phenoxy phthalocyanine

Ginsenoside F1 administration promotes UCP1-dependent fat browning and ameliorates obesity-associated insulin resistance

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Food Science and Human Wellness 2023年第6期12卷 2061-2072页

作者： Yuhan Meng weili li Chenxing Hu Si Chen Haiyang li Feifei Bai Lujuan Zheng Ye Yuan Yuying Fan Yifa Zhou Engineering Research Center of Glycoconjugates of Ministry of Education Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural DrugsSchool of Life SciencesNortheast Normal UniversityChangchun 130024China

Obesity-induced type 2 diabetes is mainly due to excessive free fatty acids leading to insulin *** thermogenesis is regarded as an effective strategy for hypolipidemia and *** is a natural active component in Panax ginseng ***,and some of them enhance ***,there are few studies on the mechanism and target of ginsenosides enhancing *** thermogenic protein uncoupling protein 1(UCP1)-luciferase reporter assay,we identifi ed ginsenoside F1 as a novel UCP1 activator in the ginsenosides *** pull down assay and inhibitor interference,we found F1 binds toβ3-adrenergic receptors(β3-AR)to enhance UCP1 expression via cAMP/PKA/CREB *** also investigated the ability of F1 on energy metabolism in obesity-induced diabetic mice,including body weight,body composition and energy *** results of proteomics showed that F1 signifi cantly up-regulated thermogenesis proteins and lipolytic proteins,but down-regulated fatty acid synthesis *** F1 increased thermogenesis and ameliorated insulin resistance specifi cally by promoting the browning of white adipose tissue in obese ***,ginsenoside F1 improves norepinephrine-induced insulin resistance in adipocytes and hepatocytes,and shows a stronger mitochondria respiration ability than *** fi ndings suggest that ginsenoside F1 is a promising lead compound in the improvement of insulin resistance.

关键词： Ginsenoside F1 Uncoupling protein 1 β3-Adrenergic receptor White adipose tissue browning Insulin resistance

Copper-cobalt-nickel oxide nanowire arrays on copper foams as self-standing anode materials for lithium ion batteries

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Chinese Chemical Letters 2021年第2期32卷 938-942页

作者： Xiaomin Kang Guodong Fu Xuewan Wang lin Shao weili li Chi-Wing Tsang Xiao-Ying Lu Xian-Zhu Fu Jing-li Luo Shenzhen Key Laboratory of Polymer Science and Technology Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and Engineering.Shenzhen UniversityShenzhen 518060China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province.College of Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Faculty of Science and Technology Technological and Higher Education Institute of Hong KongHong KongChina Department of Chemical and Materials Engineering University of AlbertaEdmontonAlbertaT6C 1H9Canada

Numerous scientists are in the pursuit of energy storage materials with high energy and high power density by assembly of electrochemically active materials into conductive scaffolds,owing to the emerging need for next-generation energy storage *** this architectures,the active materials bonded to the conductive scaffold can provide a robust and free-standing structure,which is crucial to the fabrication of materials with high gravimetric ***,hierarchical copper-cobalt-nickel ternary oxide(CuCoNi-oxide) nanowire arrays grown from copper foam were successfully fabricated as freestanding anode materials for lithium ion batteries(liBs).CuCoNi-oxide nanowire arrays could provide more active sites owing to the hyperbranched structure,leading to a better specific capacity of 1191 mAh/g,cycle performance of 73% retention in comparison to CuO nanowire structure,which exhibited a specific capacity of 1029 mAh/g and capacity retention of 43%,respectively.

关键词： Binder-free electrode Cuo array Copper-cobalt-nickel oxide(CuCoNi-oxide) Volumetric Effect lithium ion batteries