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Synthesis and Molecular Structure of Phosphorus-sulfur Hybrid Atom Ligand and Their Palladium Complexes With the Studies on the C—H Bond Activation and Photochemical Carbonylation Reaction of Benzene

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Science China Chemistry 1993年第5期36卷 513-525页

作者：张良辅杨军黄德建李广年 Chengdu Institute of Organic Chemistry Academia Sinica Chengdu 610015 PRC

In this paper, a novel and ideal synthetic method of the phosphorus and sulfur hybrid atom ligand is reported. The speciality of this method is that the by-products of some reactions could be used circularly as starting materials in the synthetic route. Further, we synthesized a series of organopalladium complexes containing these hybrid atom chelate ligands, among them the molecular structures of novelorganopalladium complexes Pd（（i-Pr）2-P（CH2）2SEt）Cl2, Pd（Et2P（CH2）2SEt）Cl2 and Pd（Ph2P（CH2）2SEt）Cl2 were determined by using the X-ray single crystal diffraction method. We first used the organotransition metal complexes containing phosphorus and sulfur hybrid atom ligands to activate the σ-C—H bond, and researched the catalytic activity, i.e. the photochemical carbonylation of benzene was catalyzed by these palladium complexes.

关键词： phosphorus and sulfur hybrid atom ligand organopalladium complex molecular structure C—H bond activation.

MoS2 nanorods with inner caves through synchronous encapsulation of sulfur for high performance Li–S cathodes

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Journal of Energy Chemistry 2020年第6期29卷 18-24,I0002页

作者： Yikun Yi Zechen Liu Pu Yang Tao Wang Xuewen Zhao Hongyang Huang Yonghong Cheng Jinying Zhang Mingtao Li Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049ShaanxiChina State Key Laboratory of Electrical Insulation and Power Equipment Center of Nanomaterials for Renewable Energy(CNRE)School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049ShaanxiChina Guangdong Xi’an Jiaotong University Academy Foshan 528300GuangdongChina School of Environment and Architecture Dongguan University of TechnologyDongguan 523808GuangdongChina

Lithium–sulfur(Li–S)batteries have become one of the most promising candidates for next-generation batteries owing to their high specific capacity,low cost,and environment-friendliness.Many efforts have been made to mitigate the"shuttle effect"through physical adsorption and chemical bonding.MoS2 has been proposed as a cathode material to provide effective anchoring sites for lithium polysulfides(Li PSs),but is still limited by its layer structure.Herein,we designed novel MoS2 nanorods with inner caves based on our previous work,and performed synchronous encapsulation of sulfur during the synthesis process.The outer MoS2 tubular shells physically inhibit the outward diffusion of polysulfide species while the inner particles chemically anchor the polysulfides to prevent shuttling.As the cathode matrix in Li–S batteries,the electrochemical results deliver a high initial discharge capacity of 1213 mAhg^-1 for sulfur at 0.1 C.After cycling at 1 C for 300 cycles,the cells exhibit a capacity decay of only 0.076%per cycle and high average coulombic efficiency over 95%.The tubular MoS2 structure is an innovative and appealing design,which could be regarded as a prospective substrate for the improved performance of Li–S batteries.

关键词： MoS2 nanorod Inner caves Synchronous encapsulation of sulfur Cathode matrix

Suspension calcination and alkali leaching of low-grade high-sulfur bauxite:Desulfurization, mineralogical evolution and desilication

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 602-610页

作者： Hong-fei Wu Jun-qi Li Chao-yi Chen Fei-long Xia Zhen-shan Xie Department of Metallurgical Engineering College of Materials and MetallurgyGuizhou UniversityGuiyang 550025China Guizhou Province Key Laboratory of Metallurgical Engineering and Process Energy Saving Guiyang 550025China

To enable the utilization of low-grade and high-sulfur bauxite, the suspension calcination was used to remove the sulfur and the activate silica minerals, and the calcinated bauxite was subjected to a desilication process in Na OH solution under atmospheric pressure. The desulfurization and desilication properties and mineralogical evolution were studied by X-ray diffraction, thermogravimetry–differential thermal analysis, scanning electron microscopy, and FactSage methods. The results demonstrate that the suspension calcination method is efficient for sulfur removal: 84.21% of S was removed after calcination at 1000°C for 2 min. During the calcination process, diaspore and pyrite were transferred to α-Al2O3, magnetite, and hematite. The phase transformation of pyrite follows the order FeS2 → Fe3O4 → Fe2O3, and the iron oxides and silica were converted into iron silicate. In the alkali-soluble desilication process, the optimum condition was an alkali solution concentration of 110 g/L, a reaction time of 20 min, and a reaction temperature of 95°C. The corresponding desilication ratio and alumina loss ratio were 44.9% and 2.4%, respectively, and the alumina-to-silica mass ratio of the concentrate was 7.9. The Al2O3·2SiO2, SiO2, and Al2O3 formed during the calcination process could react with Na OH solution, and their activity decreased in the order of Al2O3·2 SiO2, SiO2, and Al2O3.

关键词： low-grade bauxite sulfur suspension calcination alkali-soluble desilication Bayer process

A direct H2O2 production based on hollow porous carbon sphere-sulfur nanocrystal composites by confinement effect as oxygen reduction electrocatalysts

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Nano Research 2019年第10期12卷 2614-2622页

作者： Guanyu Chen Jiwei Liu Qingqing Li Pengfei Guan Xuefeng Yu Linshen Xing Jie Zhang Renchao Che Laboratory of Advanced Materials Department of Materials Science and Collaborative Innovation Center of Chemistry for Energy Materials(iChem)Fudan UniversityShanghai 200438China Beijing Computational Science Research Center Beijing 100193China Innovative Center for Advanced Materials(ICAM) Hangzhou Dianzi UniversityHangzhou 310012China

Carbon-sulfur composites have draw n in creasing interest in various fields including electrocatalysis because of their unique structures.However,carb on-sulfur composite with tiny sulfur nano crystals has still received little attention.Herein,hollow porous carb on sphere-sulfur composite(HPCS-S)which possesses excellent electrochemical performance towards H2O2 has been prepared for the first time via a simple silica template method.The 2-5 nm sulfur nan ocrystals being restricted in the cha nnel of the hollow porous carb on spheres are un der a strong compressive stress,which was further con firmed by high-resoluti on tran smissi on electr on microscopy(HRTEM)and GPA.The HPCS-S nano crystals show better con ductivity tha n amorphous sulfur clusters because of the reducti on of the steric hindrance which efficie ntly promotes the electron transportation.Consequently,the higher activity and selectivity towards the 2e^oxygen reduction reaction(ORR)to H2O2 in alkaline solution was obtained.The H2O2 selectivity rises from 20%to over 70%after the sulfur addition and the H2O2 production rate achieves 183.99 mmol-gcataiyst-1 with the Faradaic efficiency of 70%.Furthermore,performance enhancement mechanism was also investigated using the den sity functional theory(DFT)calculatio ns.After the in troduci ng of sulfur nano crystals,the appeara nee of S-S bond greatly decreases the overpotential compared with S-doping,which results in significant enhancement of the electrocatalytic property.Consequently,the HPCS-S can be an efficient H2O2 production electrocatalyst in alkaline solution.

关键词： sulfur nanocrystal hydrogen peroxide production carbon sphere oxygen reduction reaction

A sulfur–microporous carbon composite positive electrode for lithium/sulfur and silicon/sulfur rechargeble batteries

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Progress in Natural Science:Materials International 2015年第6期25卷 612-621页

作者： Takuya Takahashi Masaki Yamagata Masashi Ishikawa Department of Chemistry and Materials Engineering Faculty of ChemistryMaterials and BioengineeringKansai University

sulfur is an advantageous material as a promising next-generation positive electrode material for high-energy lithium batteries due to a high theoretical capacity of 1672 m A h g 1although its discharge potential is somewhat modest:ca.2 V vs Li/Lit.However,a sulfur positive electrode has some crucial problems for practical use,which are mainly attributed to the dissolution of its intermediate products in charge–discharge processes.In order to resolve the dissolution problem of lithium polysulfide,we attempted to synthesize a sulfur–microporous activated carbon(AC) composite positive electrode.Moreover,we have systematically researched the battery performance of sulfur–microporous AC positive electrode with variations of electrolytes as well as negative electrodes,and found its promising positive electrode performance for a nextgeneration rechargeable battery.

关键词： sulfur Micropore Ionic liquid Silicon Lithium-ion battery

Biomass-derived nitrogen-doped hierarchical porous carbon as efficient sulfur host for lithium–sulfur batteries

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Journal of Energy Chemistry 2020年第5期29卷 61-67页

作者： Qinghuiqiang Xiao Gaoran Li Minjie Li Ruiping Liu Haibo Li Pengfei Ren Yue Dong Ming Feng Zhongwei Chen Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing 100083China Department of Chemical Engineering University of WaterlooWaterloo N2L3G1OntarioCanada Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun 130103JilinChina

Lithium-sulfur(Li-S) battery is a potential energy storage technology with high energy density and low cost. However, the gap between theoretical expectation and practical performance limits its wide implementation. Herein, we report a nitrogen-doped porous carbon derived from biomass pomelo peel as sulfur host material for Li-S batteries. The hierarchical porous architecture and the polar surface introduced by N-doping render a favorable combination of physical and chemical sulfur confinements as well as an expedite electron/ion transfer, thus contributing to a facilitated and stabilized sulfur electrochemistry. As a result, the corresponding sulfur composite electrodes exhibit an ultrahigh initial capacity of 1534.6 mAh g^-1, high coulombic efficiency over 98% upon 300 cycles, and decent rate capability up to 2 C. This work provides an economical and effective strategy for the fabrication of advanced carbonaceous sulfur host material as well as the significant improvement of Li-S battery performance.

关键词： Biomass-derived material Porous carbon Lithium sulfur batteries Electrochemical performance

Preparation of nitrogen and sulfur co-doped ultrathin graphitic carbon via annealing bagasse lignin as potential electrocatalyst towards oxygen reduction reaction in alkaline and acid media

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Journal of Energy Chemistry 2019年第7期28卷 33-42页

作者： Yixing Shen Feng Peng Yonghai Cao Jianliang Zuo Hongjuan Wang Hao Yu School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640GuangdongChina Guangzhou Key Laboratory for New Energy and Green Catalysis School of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou 510006GuangdongChina

Renewable lignin used for synthesizing materials has been proven to be highly potential in specific electrochemistry.Here,we report a simple method to synthesize nitrogen and sulfur co-doped carbon nanosheets by using bagasse lignin,denoted as lignin-derived carbon(LC).By adjusting the ratio of nitrogen source and annealing temperature,we obtained the ultrathin graphitic lignin carbon(LC-4-1000)with abundant wrinkles with high surface area of 1208 m2g_1 and large pore volume of 1.40 cm3g_1.In alkaline medium,LC-4-1000 has more positive half-wave potential and nearly current density compared to commercial Pt/C for oxygen reduction reaction(ORR).More importantly,LC-4-1000 also exhibits comparable activity and superior stability for ORR in acid medium due to its high graphitic N ratio and a direct four electron pathway for ORR.This study develops a cost-effective and highly efficient method to prepare biocarbon catalyst for ORR in fuel cells.

关键词： Electrocatalyst Biocarbon Lignin Nitrogen and sulfur co-doped carbon Oxygen reduction reaction

Separator coatings as efficient physical and chemical hosts of polysulfides for high-sulfur-loaded rechargeable lithium–sulfur batteries

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Journal of Energy Chemistry 2020年第5期29卷 51-60页

作者： Masud Rana Ming Li Qiu He Bin Luo Lianzhou Wang Ian Gentle Ruth Knibbe Materials Engineering School of Mechanical and Mining EngineeringThe University of QueenslandSt LuciaQLD 4072Australia Nanomaterials Centre School of Chemical Engineering and Australian Institute for Bioengineering and NanotechnologySt LuciaThe University of Queensland QLD 4072Australia School of Chemistry and Molecular Biosciences Faculty of ScienceThe University of QueenslandSt LuciaQLD 4072Australia State School Key Laboratory of Silicate Materials for Architectures International School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070HubeiChina

Lithium-sulfur batteries(LSBs)are promising alternative energy storage devices to the commercial lithium-ion batteries.However,the LSBs have several limitations including the low electronic conductivity of sulfur(5×10^-30S cm^-1),associated lithium polysulfides(PSs),and their migration from the cathode to the anode.In this study,a separator coated with a Ketjen black(KB)/Nafion composite was used in an LSB with a sulfur loading up to 7.88 mg cm^-2to mitigate the PS migration.A minimum specific capacity(Cs)loss of 0.06%was obtained at 0.2 C-rate at a high sulfur loading of 4.39 mg cm^-2.Furthermore,an initial areal capacity up to 6.70 mAh cm^-2 was obtained at a sulfur loading of 7.88 mg cm^-2.The low Cs loss and high areal capacity associated with the high sulfur loading are attributed to the large surface area of the KB and sulfonate group(SO3^-)of Nafion,respectively,which could physically and chemically trap the PSs.

关键词： Lithium-sulfur battery Separator coating Physical and chemical confinement Self-discharge High sulfur loading Specific capacity loss High areal capacity

In-situ sulfur isotope and trace element of pyrite constraints on the formation and evolution of the Nibao Carlin-type gold deposit in SW China

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Acta Geochimica 2019年第4期38卷 555-575页

作者： Jinxiang Li Chenghai Zhao Yong Huang Yuzhou Zhuo Jinwei Li State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The fault-controlled Nibao Carlin-type gold deposit,together with the strata-bound Shuiyindong deposit,comprise a significant amount of the disseminated gold deposits in southwestern Guizhou Province,China.Five main types and two sub-types of pyrite at the Nibao deposit(Py1a/Py1b,Py2,Py3,Py4,Py5)were distinguished based on detailed mineralogical work.Py1,Py2and Py3 are Au-poor,whereas Py4 and Py5 are Au-rich,corresponding to a sedimentary and hydrothermal origin,respectively.Through systematic in situ analyses of NanoSIMS sulfur isotopes,the framboid pyrite Py1a with negative δ^34S values(-53.3 to-14.9%)from the Nibao deposit were found to originate from bacterial sulfate reduction(BSR)processes in an open and sulfate-sufficient condition while the superheavy pyrite Py1b(73.7–114.8%)is probably due to the potential influence of closed-system Rayleigh fractionation or the lack of preservation of deepsea sediments.Data of Py2 and Py3 plot within the area of S isotope compositions from biogenic and abiogenic sulfate reduction.In view of few coeval magmatic rocks in the mining district,the near zero δ^34S values of the Au-rich pyrites(Py4 and Py5)may discount the potential involvement of magmatic but metamorphic or sedimentary origin.LA-ICP-MS and TEM work show that Au in ore-related pyrite is present as both nanoparticles and structurally bound.LA-ICP-MS analyses show that the Au-rich pyrite also contains higher As,Cu,Sb,Tl and S than other types of pyrite,which inferred a distal manifestation of deep hydrothermal mineralization systems.

关键词： Nibao Carlin-type gold deposit Pyrite NanoSIMS LA-ICP-MS sulfur isotopes