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sulfur-encapsulated in heteroatom-doped hierarchical porous carbon derived from goat hair for high performance lithium–sulfur batteries

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Journal of Energy Chemistry 2019年第3期28卷 121-131页

作者： Juan Ren Yibei Zhou Huali Wu Fengyu Xie Chenggang Xu Dunmin Lin College of Chemistry and Materials Science Sichuan Normal University

Biomass-derived carbon materials have aroused widespread concern as host material of sulfur to enhance electrochemical performances for lithium–sulfur batteries. Herein, goat hair, as a low-cost and eco-friendly precursor, is employed to fabricate cauliflower-like in-situ nitrogen, oxygen and phosphorus tri-doped porous biomass carbon(NOPC) by a facile activation with H_3PO_4 and carbonization process.The morphology and microstructure of NOPC can be readily tuned by altering pyrolysis temperature. The as-prepared NOPC matrix material carbonized at 600 °C possesses 3D hierarchical porous structure, high specific surface area(535.352 m^2 g^(-1)), and appropriate pore size and pore size distribution. Encapsulating sulfur into the NOPC depends on a stem-melting technology as cathode materials of Li–S batteries. Due to the synergistic effect of special physical structure and inherent tri-doping of N, O and P, electrons and ions transfer and utilization of active sulfur in the materials are improved, and the shuttle behaviors of soluble lithium polysulfides are also mitigated. Consequently, the S/NOPC-600 composite exhibits excellent electrochemical performance, giving a high initial discharge capacity of 1185 mA h g^(-1) at 0.05 C and maintaining a relatively considerable capacity of 489 m A h g^(-1) at 0.2 C after 300 cycles. Our work shows that a promising candidate for cathode material of Li–S batteries can be synthesized using low-cost and renewable biomass materials by a facile process.

关键词： Biomass-derived carbon materials Goat hair Nitrogen Oxygen and phosphorus tri-doping Lithium sulfur batteries

sulfur distribution in preparation of high titanium ferroalloy by thermite method with different CaO additions

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Rare Metals 2019年第8期38卷 793-799页

作者： Chu Cheng Zhi-He Dou Ting-An Zhang Jian-Ming Su Hui-Jie Zhang Yan Liu Li-Ping Niu School of Metallurgy Northeastern University Shenyang 110819 China Key Laboratory of Ecological Utilization of Multi-Metal Intergrown Ores of Ministry of Education Northeastern University Shenyang 110819 China

Ferrotitanium is used as a deoxidizer and alloying agent during steelmaking process,which has a high demand for sulfur control.sulfur was introduced from raw materials in the process of producing ferrotitanium by thermite method,where CaO was used as fluxing agent.At the same time,CaO has a great desulfurization capability.Effects of CaO addition on the distribution of sulfur in high titanium ferroalloy prepared by thermite method were studied in this work.The equilibrium diagram of Ti-AlFe-S system was calculated by FactSage 6.4 software package with FactPS and FTmisc database.The alloy and slag samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),inductively coupled plasma atomic emission spectrometer(ICP-AES),X-ray fluorescence(XRF)and high-frequency infrared ray carbon sulfur analyzer.The result indicates that the sulfur in the alloy firstly exists in the form of liquid FeS,thereafter TiS(s)and eventually Ti2 S(s)during cooling.The sulfur is mainly distributed in the alloy,and only a small amount of sulfur remains in the slag.Moreover,it is noted that the sulfur in the alloy does not distribute homogeneously,and it exists in the form of solid solution phase,(Ti,Al,Fe)S.S content in the slag,the sulfur capacity of the slag and the sulfur distribution ratio(LS)all increase with the increment of CaO addition,while S content in alloys decreases.

关键词： Desulfurization sulfur partition ratio Optical basicity High titanium ferroalloy Thermite method

Efect of operating parameters on sulfide biotransformation to sulfur

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Journal of Environmental Sciences 2013年第12期25卷 2417-2421页

作者： Weiguo Liu Cunzhen Liang Jiaqing Chen Ling Zhu College of Resources and Environmental Engineering Wuhan University of Technology Department of Environmental Engineering Beijing Institute of Petrochemical Technology

A laboratory-scale bioreactor with polyethylene semi-soft packing was constructed and utilized to determine the efficlency of sulfide biotransformation to sulfur under various operating parameters. Sodium sulfide dissolved in tap water was pumped into the bioreactor as sulfide for biological desulfurization. The sulfide, sulfur and sulfate-S in the effluent and the sulfide purged as gas-phase HzS were determined to investigate the effects of operating parameters, such as pH, DO, hydraulic retention time （HRT）, temperature and salinity, on the sulfide oxidation products. The activity of bacteria was highest at pH 7.8-8.2. The maximal sulfide removal load was 7.25 kg/（m^3·day）, with a 322.07 mg/L influent sulfide concentration and 4.80 mg/L DO. The increase of DO value corresponds to a decrease in the sulfur yield. The reactor had the highest sulfide removal load and sulfur yield at 2.55 mg/L DO. HRT had little effect on desulfurization efficiency when the sulfide removal load was kept constant. The most effective desulfurization temperature was 33℃. The sulfide removal load decreased from 2.85 to 0.51 kg/（m^3.day） with increasing salinity from 0.5% to 2.5% （m/m）.

关键词： sulfide sulfur biotransformation operating parameters

Electrochemical Selective Oxidative Synthesis of Diversified sulfur Heterocycles fromβ-Ketothioamides

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Chinese Journal of Chemistry 2021年第7期39卷 1831-1837页

作者： Li-Rong Wen Ning-Ning Wang Wu-Bo Du Ming-Zhe Zhu Chao Pan Lin-Bao Zhang Ming Li State Key Laboratory Base of Eco-Chemical Engineering College of Chemistry and Molecular EngineeringQingdao University of Science&TechnologyQingdaoShandong266042 China

Main observation and conclusion A general and practical protocol for the construction of diversified sulfur heterocycles has been described through organic electrosynthesis means.In undivided cell,dihydrothiophenes,thiazolines and 1,4-dithiines could be easily generated from various availableβ-ketothioamides under metal-free and external oxidant-free conditions.

关键词： sulfur Synthesis design Annulation Metal-free Electrosynthesis

Comprehensive analysis of the chemical constituents in sulfur-fumigated Lonicerae Japonicae Flos using UHPLC-LTQ-Orbitrap mass spectrometry

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Chinese Journal of Natural Medicines 2020年第2期18卷 148-160页

作者： LIU Zi-Han WANG Yu-Qi MEI Xiao-Dan WANG Fei YANG Xian-Zhao LI Xiao-Dong JIANG Feng ZHANG Jia-Yu School of Chinese Pharmacy Beijing University of Chinese MedicineBeijing 102488China BUCM Institute of Liver Diseases Dongzhimen Hospital affiliated to Beijing University of Chinese MedicineBeijing 100700China Department of Hepatology Hubei Provincial Hospital of Traditional Chinese MedicineWuhan 430061China School of Pharmacy Binzhou Medical UniversityYantai 264003China

Lonicerae Japonicae Flos(LJF),a kind of traditional Chinese medicines(TCMs),has functions of detoxifying and evacuating heat.In the study,a method based on ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS)was developed for the chemical constituent analysis of organic acids,flavonoids,iridoids and new-generated compounds in sulfur-fumigated LJF(SF-LJF).Based on the accurate mass measurement(sulfur-containing derivatives).In addition,5-CQA(5-caffeoylquinic acid,chlorogenic acid)was chosen to be sulfur-fumigated for the result validation.It was found that the most significant change of LJF after sulfur fumigation was the occurrence of sulfate or sulfite esterification reactions,which resulted in the emergence of many new sulfur-containing components.Our results demonstrated that the established method was a useful and efficient analytical tool to comprehensively characterize the material basis of SF-LJF,and also an excellent guidance of quality control about LJF.

关键词： sulfur fumigation Lonicerae Japonicae Flos Chemical components analysis UHPLC-LTQ-Orbitrap MS

sulfur isotopic composition and source identification of atmospheric environment in central Zhejiang,China

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Science China Earth Sciences 2010年第11期53卷 1717-1725页

作者： Zhang MiaoYun Wang ShiJie Ma GuoQiang Zhou HuaiZhong Fu Jun Chinese Acad Sci Inst Geochem State Key Lab Environm Geochem Guiyang 550002 Peoples R China Jinhua Environm Monitoring Ctr Jinhua 321013 Peoples R China Environm Monitoring Ctr Zhejiang Prov Hangzhou 310012 Zhejiang Peoples R China

sulfur dioxide and sulfate aerosols in the atmosphere are significant factors leading to acidification of the atmospheric environment and worsening the pollution of acid deposition. Because of the "fingerprint" characteristics of the stable sulfur isotopic composition, sulfur isotope has been widely adopted in environmental researches concerning sulfur cycle and source identification. In this study, the atmospheric environment of Jinhua City, central Zhejiang Province, was continuously monitored, and the sulfur isotopic composition of SO2 and sulfate aerosols in the atmosphere was analyzed. The results indicate that the variation of δ34S values for SO2 ranges from 1.0‰ to 7.5‰, and annual average is 4.7‰±2.3‰, whereas that of sulfate aerosols ranges from 6.4‰ to 9.8‰,and annual average is 8.1‰±1.0‰. The δ 34S values for SO2 have significant seasonal variations, which are 7.0‰ in winter and 3.3‰ in summer. These variations cannot be attributed to a single factor, and we suggest a temperature-dependent isotope equilibrium fractionation and elevated biogenic sulfur emissions of isotopically light S in summer may be the main controlling mechanisms. Furthermore, we also discuss the δ 34S model of atmospheric SO2 oxidation to form sulfate, and suggest that heterogeneous oxidation dominates in the oxidation reactions of atmospheric SO2 in the central Zhejiang Province. We further suggest that the relative humidity in the atmosphere plays an important role in the oxidation mechanism of atmospheric SO2.

关键词： sulfur isotope SO2 aerosol homogeneous oxidation heterogeneous oxidation

Elemental sulfur and Dimethyl Sulfoxide-Promoted Oxidative Cyclization of Trifluoroacetimidohydrazides with Methylheta-renes for the Synthesis of 3-Hetaryl-5-trifluoromethyl-1,2,4-triazoles

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Chinese Journal of Chemistry 2021年第12期39卷 3443-3447页

作者： Jiajun Zhang Jianhua Tang Zhengkai Chen Xiao-Feng Wu Department of Chemistry Key Laboratory of Surface&Interface Science of Polymer Materials of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhouZhejiang 310018China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China Leibniz-lnstitutfurKatalysee.V. Albert-Einstein-Stra6e 29a18059 RostockGermany

A metal-free approach for the synthesis of 3-hetaryl-5-trifluoromethyl-1,2,4-triazoles via sulfur/dimethyl sulfoxide-promoted oxidative cyclization of readily available trifluoroacetimidohydrazides with methylhetarenes has been developed.This transformation proceeds in cascade sulfur-mediated generation of thioaldehyde,condensation,intramolecular cyclization and oxidative aromatization sequence.

关键词： Heterocycles Oxidation Solvent effects sulfur Trifluoroacetimidohydrazides

Unusual Band Splitting and Superconducting Gap Evolution with sulfur Substitution in FeSe

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Chinese Physics Letters 2022年第5期39卷 76-81页

作者：杨媛媛王奇思段绍峰沃弘樑黄超之王石崇顾凌霄钱冬赵俊张文涛 Key Laboratory of Artifcial Structures and Quantum Control(Ministry of Education) Shenyang National Laboratory for Materials ScienceSchool of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433China Institute of Nanoelectronics and Quantum Computing Fudan UniversityShanghai 200433China

High-resolution angle-resolved photoemission measurements were taken on FeSe;S;(x=0,0.04,and 0.08)superconductors.With an ultrahigh energy resolution of 0.4 meV,unusual two hole bands near the Brillouin-zone center,which was possibly a result of additional symmetry breaking,were identified in all the sulfur-substituted samples.In addition,in both of the hole bands highly anisotropic superconducting gaps with resolution limited nodes were evidenced.We find that the larger superconducting gap on the outer hole band is reduced linearly to the nematic transition temperature while the gap on the inner hole is nearly S-substitution independent.Our observations strongly suggest that the superconducting gap increases with enhanced nematicity although the superconducting transition temperature is not only governed by the pairing strength,demonstrating strong constraints on theories in the FeSe family.

关键词： bands sulfur substituted

Graphene/RuO2 nanocrystal composites as sulfur host for lithium-sulfur batteries

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Journal of Energy Chemistry 2019年第8期28卷 204-211,I0007页

作者： Jian-Qiu Huang Jiaqiang Huang Woon Gie Chong Jiang Cui Shanshan Yao Baoling Huang Jang-Kyo Kim Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology

An optimized graphene/RuO2/S composite is prepared by hydrothermal growth of RuO2 particles on graphene oxide sheets as the positive electrode for rechargeable lithium-sulfur batteries. The electrode with 6.1 wt% RuO2 nanocrystals and a high sulfur content of 79.0 wt% delivers an optimal electrochemical performance with high residual capacities of 508 mAh g-1 after 200 cycles and 389 m Ah g-1 after800 cycles at 1 C with a low capacity decay of 0.054%. The RuO2 nanocrystals promote the redox reaction kinetics and facilitate the transformation of sulfur chemistry, leading to large improvements in reversibility and rate capability of the composite electrode. The density functional theory calculations signify the formation of Li–O and Ru–S bonds through chemical interactions between RuO2 and Li polysulfides while the adsorption energies between graphene and polysulfide species are much higher in the presence of RuO2 than that of the neat graphene acting alone. These discoveries support the efficient entrapment of polysulfides by the composite electrode to the benefit of enhanced cyclic stability of the battery.

关键词： Enhanced redox reaction kinetics Polysulfide adsorption Density functional theory Lithium sulfur batteries High sulfur content