检索结果-南通市图书馆

Synthesis and electrochemical properties of Li FePO_(4) cathode material by ionic thermal method using eutectic mixture of tetramethyl ammonium chloride-urea

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2021年第12期40卷 3477-3484页

作者： Si-Nan Li shao-hua luo Liu Yang Qing Wang Ya-Hui Zhang Xin Liu School of Materials Science and Engineering Northeastern UniversityShenyang 110819China School of Resources and Materials Northeastern University At QinhuangdaoQinhuangdao 066004China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province Qinhuangdao 066004China

In this study, the LiFePO_(4) cathode was synthesized by the ionic thermal method using the deep eutectic mixture of tetramethyl ammonium chloride and urea. The synthetic conditions were systematically investigated by orthogonal experiments, which indicate that the optimal reaction time, reaction temperature, molar ratio of Li to DES and rotate speed are 96 h, 220 ℃, 1:14 and20 r·min^(-1), respectively. X-ray diffraction(XRD), scanning electron microscope(SEM) and transmission electron microscope(TEM) were characterized to investigate the crystalline structure and morphology of the obtained materials, indicating well-crystallized LiFePO_(4) with olivine structure. And the physical properties of LiFePO_(4) were explored through Fourier transform infrared spectroscopy(FTIR),57 Fe Mo¨ ssbauer absorption spectra and Raman spectra. An initial discharge capacity can reach 151 m Ah·g^(-1) at 0.1 C rate for LiFePO_(4) following by calcining at 600 ℃ under the optimal conditions, and it retains 125.1 m Ah·g^(-1) after 100 cycles. These results demonstrated that the addition of ionic liquids can improve the rate performance, cycle performance and ion diffusion rate of LiFePO_(4).

关键词： LiFePO_(4) Deep eutectic solvents Ionic thermal method Orthogonal experiments Electrochemical performance

In situ synthesis of Co_(3)O_(4)nanoparticles confined in 3D nitrogendoped porous carbon as an efficient bifunctional oxygen electrocatalyst

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2020年第12期39卷 1383-1394页

作者： Zhi-Yuan Wang Shun-Da Jiang Chan-Qin Duan Dan Wang shao-hua luo Yan-Guo Liu School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Dielectric and Electrolyte Functional Material-Hebei Province Qinhuangdao 066004China

The rational exploitation of non-precious metal catalyst with high activity,strong durability and low cost for the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is of vital importance for metalair ***,a composite of Co_(3)O_(4)nanoparticles confined in three-dimensional(3 D)N-doped porous carbon(Co-NpCs)was prepared by a simple freeze-drying and in situ pyrolysis *** effect of different dosages of Co(NO_(3))_(2)on the catalytic performance was *** Co-NpC-12%exhibits the best catalytic performance(E_(1/2)=0.78 V,better stability than 20%Pt/C)in ORR and in OER among all the as-synthesized ***,it also exhibits the best bifunctional activity(ΔE=0.849 V).The excellent properties of Co-NpCs are mainly due to the synergy between Co_(3)O_(4)and ***,a high Co_(3)O_(4)loading amount can boost the defect level of the N-doped hierarchical porous carbon and expose more active ***,the unique in situ pyrolysis guarantees a largearea contact between Co_(3)O_(4)and carbon as well as a strong C-O-Co bonding,which promotes charge transfer,avoids the peeling of Co_(3)O_(4)nanoparticles and effectively improves the stability of the *** work is expected to offer a feasible strategy to produce metal oxide/carbon nanocomposite and push forward the development of bifunctional electrocatalyst with high activity and stability.

关键词： Bifunctional electrocatalyst Co_(3)O_(4) Nitrogendoped porous carbon In situ synthesis

Raman spectroscopy and quantum chemical calculation on YCl_(3)-KCl molten salt system

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2023年第11期42卷 3886-3896页

作者： Can Xu Xian-Wei Hu Jiang-Yu Yu Peng-Wei Li Ai-Min Liu shao-hua luo Zhong-Ning Shi Zhao-Wen Wang Key Laboratory Ecological Metallurgy of Multimetallic Mineral‘Ministry of Education’ School of MetallurgyNortheastern UniversityShenyang110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China School of Materials Science and Engineering Northeastern UniversityShenyang110819China Department of Chemistry and Bioscience Aalborg University9220AalborgDenmark

The knowledge on the ionic structure of YCl_(3)-KCl molten system is of guiding significance for the practical production of yttrium metals and yttrium alloys via molten salt electrolysis using this system as *** this paper,the theoretical Raman spectra of the ionic groups which may exist in YCl_(3)-KCl molten system are simulated by quantum chemical calculation using Gaussian09 and Gauss View 5.0 programs based on density functional theory(DFT).Then the ionic structures of 20 mol%-60 mol%YCl_(3)-KCl molten salt systems are studied by comparing the Raman shift values of the bands in the theoretical Raman spectra of different ionic groups with the experimental spectra of this ***_(6)^(3-),Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-)and Y_(2)Cl_(9)^(3-)are thought to exist in the molten *** the increase of temperature,the relative content of YCl_(6)^(3-)ionic groups increases while those of Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-)and Y_(2)Cl_(9)^(3-)ionic groups ***,the"lifetime"of all ionic groups decreases within the temperature range of 692-730℃.Meanwhile,the relative contents of Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-)and Y_(2)Cl_(9)^(3-)increase with the increase of YCl_(3)content,while that of YCl_(6)^(3-)*** wave function analysis of the four ionic groups(YCl_(6)^(3-),Y_(2)Cl_(7)^(-),Y_(2)Cl_(8)^(2-),and Y_(2)Cl_(9)^(3-))is carried out by Multiwfn *** net charge in each group,the direction of electron migration during the formation of each group,the sites where electrophilic and nucleophilic reactions are most likely to occur in each ionic group,and the order of bond breaking during chemical reactions for the four groups are obtained.

关键词： YCl_(3)-KCl molten salt Ionic structure Raman spectroscopy Quantum chemical calculation Wave function analysis

Walnut septum-derived hierarchical porous carbon for ultra-high-performance supercapacitors

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2022年第7期41卷 2280-2291页

作者： Meng Zhou Sheng-Xue Yan Qing Wang Ming-Xiu Tan Deng-Yang Wang Zi-Qi Yu shao-hua luo Ya-Hui Zhang Xin Liu School of Materials Science and Engineering Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China Hebei Key Laboratory of Dielectric and Electrolyte Functional Material Qinhuangdao 066004China Qinhuangdao Key Laboratory of Advanced Energy Storage and Conversion Technology Qinhuangdao 066004China

The conversion of biomass waste into eco-nomical and high-performance energy storage devices receives significant ***,a facile and green method to prepare porous active carbon from walnut sep-tum is applied to the electrode materials of *** effect of chemical etching reagent(KOH)on the microstructure and specific capacitance of the porous car-bon are *** modified BC-2.0,with a KOH/walnut septum mass ratio of 2∶1,exhibits large specific surface area of 1003.9 m^(2)·g^(-1)with hierarchical micro-mesoporous ***-2.0 reveals a superior specific capacitance of 457 F·g^(-1)at 1 A·g^(-1).The flexible sym-metric supercapacitor in gel electrolyte(KOH/PVA)exhi-bits considerable synergetic energy-power output *** results indicate that walnut septum is a better precursor to obtain activated carbons relative to other biomass carbon *** large mesoporosity after activation effectively boosts the electrochemical properties of ***,the walnut septum has potential to be a superior electrode material for supercapacitors.

关键词： Activation Biocarbon Micro-mesoporous structure Supercapacitor High specific capacitance

High-entropy chemistry stabilizing spinel oxide(CoNiZnXMnLi)_(3)O_(4)(X=Fe,Cr)for high-performance anode of Li-ion batteries

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2022年第4期41卷 1265-1275页

作者： Kang-Hui Tian Chan-Qin Duan Qun Ma Xing-Long Li Zhi-Yuan Wang Hong-Yu Sun shao-hua luo Dan Wang Yan-Guo Liu School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Dielectric and Electrolyte Functional Materials Qinhuangdao 066004China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China

High entropy oxides(HEOs),as a new type of single-phase multielement solid solution materials,have shown many attractive features and promising application prospect in the energy storage ***,six-element HEOs(CoNiZnFeMnLi)_(3)O_(4) and(CoNiZnCrMnLi)_(3)O_(4) with spinel structure are successfully prepared by con-ventional solid-phase method and present outstanding lithium storage performances due to the synergy effect of various electrochemically active elements and the entropy *** contrast,(CoNiZnFeMnLi)_(3)O_(4) delivers higher initial discharge specific capacity of 1104.3 mAh·g^(−1),better cycle stability(84%capacity retention after 100 cycles at 100 mA·g^(−1)) and rate performance(293 mAh·g^(−1)at 2000 mA·g^(−1))in the ***,the full-cell assembled with(CoNiZnFeMnLi)_(3)O_(4) and LiCoO_(2)provides a reversible specific capacity of 260.2 mAh·g^(−1)after 100 cycles at 500 mA·g^(−1).Ex situ X-ray diffraction reveals the electrochemical reaction mechanism of HEOs(CoNiZnFeMnLi)_(3)O_(4),and the amorphous phase and the large amount of oxygen vacancies were obtained after the initial discharge process,which are responsible for the excellent cycle and rate *** research puts forward fresh insights for the development of advanced energy storage materials for high-performance batteries.

关键词： High entropy oxides Spinel structure Anode Lithium-ion batteries

Synthesis and performance of Li_4Ti_5O_(12) anode materials using the PVP-assisted combustion method

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2014年第12期25卷 1569-1572页

作者： Long-Jiao Chang shao-hua luo Hai-Liang Zhang Xi-Wei Qi Zhi-Yuan Wang Yan-Guo Liu Yu-Chun Zhai School of Materials and Metallurgy Northeastern University Hebei Provincial Laboratory of Dielectric and Electrolyte Functionals Materials School of Resources and Materials Northeastern University at Qinghuangdao Branch

Li4Ti5O12 was synthesized by a facile gel-combustion method（GCM） with polyvinylpyrrolidone（PVP） as the polymer chelating agent and *** structural and electrochemical properties of the sample were compared with the one prepared by the conventional solid-state reaction（SSR） through X-ray diffraction（XRD）,scanning electron microscopy（SEM）,cyclic voltammetry（CV）,charge-discharge measurements,and electrochemical impedance spectroscopy（EIS）,*** sub-microscale Li4Ti5O12 oxides,with a high phase purity and good stoichiometry,can be obtained by annealing at 800℃.The grain size is smaller than that of the samples that were power prepared by ***-ion batteries with a GCM Li4Ti5O12 anode exhibit excellent reversible capacities of 167.6,160.7,152.9,and 144.2 mAh/g,at the current densities of 0.5 C,1 C,3 C and 5 C,*** excellent cycling and rate performance can be attributed to the smaller particle size,lower charge-transfer resistance and larger lithium ion diffusion *** is therefore concluded that GCM Li4Ti5O12 is a promising candidate for applications in highrate lithium ion batteries.

关键词： Lithium ion battery Lithium titanate Combustion synthesis Polyvinylpyrrolidone

Sulfur-doped 3D hierarchical porous carbon network toward excellent potassium-ion storage performance

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2021年第9期40卷 2464-2473页

作者： Dan Wang Kang-Hui Tian Jie Wang Zhi-Yuan Wang shao-hua luo Yan-Guo Liu Qing Wang Ya-Hui Zhang Ai-Min Hao Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Dielectric Electrolyte Functional Materia-Hebei ProvinceQinhuangdao 066004China School of Resources and Materials Northeastern UniversityQinhuangdao 066004China

Carbonaceous materials are promising anode candidates for potassium-ion batteries, but currently the unsatisfactory cycling and rate performances due to the sluggish diffusion kinetic and serious structure damage during K+ insertion/extraction limit their practical application. Herein, a series of sulfur-doped porous carbons(SPCs) were prepared via a template-assisted freeze-drying followed by the carbonization and sulfuration processes at different temperatures. Among the three as-synthesized samples, SPC-600 exhibits the highest specific capacity(407 mAh·g^(-1) at 0.10 A·g^(-1)), the best rate(242 mAh·g^(-1) at 2.00 A·g^(-1)) and cycling performance(286 m Ah·g^(-1) after 800 cycles at 0.50 A·g^(-1)). All the SPCs display higher capacities than the undoped carbon materials. The excellent electrochemical performance of SPC can be ascribed to the abundant three-dimensional porous structure together with S-doping in the disordered carbon, which is favor of providing adequate reaction active sites as well as fast ion/electron transport paths. The density functional theory(DFT) calculations further demonstrate that the sulfurdoping can promote K-ion adsorption and storage. Meanwhile, the kinetic analyses reveal that surface-induced capacitive mechanism dominates the K-ion storage process in SPCs, which contributes to ultrafast charge storage. This work provides an effective strategy for fabricating highperformance potassium-ion storage electrode materials.

关键词： Potassium-ion batteries Porous carbon Sulfur-doping Density functional theory(DFT)calculations

Transformation and leaching kinetics of silicon from low-grade nickel laterite ore by pre-roasting and alkaline leaching process

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2018年第1期28卷 169-176页

作者： Wen-ning MU Xiu-yuan LU Fu-hui CUI shao-hua luo Yu-chun ZHAI School of Resources and Materials Northeastern University at Qinhuangdao Qinhuangdao 066004 China Key Laboratory of Resources Cleaner Conversion and Efficient Utilization at Qinhuangdao City Qinhuangdao 066004 China School of Metallurgy Northeastern University Shenyang 110819 China

The mineralogical phase transformation of a low-grade nickel laterite ore during pre-roasting process and the extraction of silicon during alkaline leaching process were *** results indicate that the reaction activity of nickel ores is effectively improved by pre-roasting at650°C for2h,because of the transformation of lizardite into magnesium olivine and *** finely ground ore samples(44-61μm)pre-roasted firstly react with sodium hydroxide solution(60g/L)with a solid/liquid ratio of1:5at140°C for120min,the extraction of silicon can reach89.89%,and the other valuable elements of magnesium,iron and nickel are accumulated in the solid *** leaching kinetics of nickel laterite ore can be described successfully by the diffusion through the product layer control *** activation energy is calculated to be11.63kJ/mol and the kinetics equation can be expressed as1-3(1-x)2/3+2(1-x)=13.53×10-2exp[-11.63/(RT)]t.

关键词： low-grade nickel laterite ore silicon extraction mineralogical phase transformation alkaline leaching kinetics

A novel synthetic route for LiFePO_4/C cathode materials by addition of starch for lithium-ion batteries

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2007年第2期18卷 237-240页

作者： shao hua luo, Zi Long Tang, Jun Biao Lu, Zhong Tai Zhang State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China [a]State Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and Engineering Tsinghua University Beijing 100084 China [b]Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China

LiFePO4/Carbon composite cathode material was prepared using starch as carbon source by spray-pelleting and subsequent pyrolysis in N2. The samples were characterized by XRD, SEM, Raman, and their electrochemical performance was investigated in terms of cycling behavior. There has a special micro-morphology via the process, which is favorable to electrochemical properties. The discharge capacity of the LiFePO4.C composite was 170 mAh g-1, equal to the theoretical specific capacity at 0.1 C rate. At 4 C current density, the specific capacity was about 80 mAh g-1, which can satisfy for transportation applications if having a more flat discharge flat.

关键词： Lithium-ion batteries Cathode material Carbon coated LiFePO4 Spray-pelleting