Highly active Fe_7S_8 encapsulated in N-doped hollow carbon nanofibers for high-rate sodium-ion batteries
作者：
Zhang, Chengzhi;Wei, Donghai;Wang, Fei;Zhang, Guanhua* ;Duan, Junfei;...
期刊：
能源化学(英文) ,2021年53(02):26-35 ISSN：2095-4956
通讯作者：
Zhang, Guanhua;Han, Fei;Liu, Jinshui
作者机构：
[Han, Fei; Wang, Fei; Zhang, Chengzhi; Liu, Jinshui] Hunan Univ, Coll Mat Sci & Engn, Hunan Prov Key Lab Adv Carbon Mat & Appl Technol, Changsha 410082, Hunan, Peoples R China.;[Han, Fei; Zhang, Guanhua; Duan, Huigao; Wei, Donghai; Zhang, GH; Han, F; Liu, JS] Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[Wei, Donghai; Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Zhang, GH; Han, F; Liu, JS] H;Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词：
Anodes;Carbon nanofibers;Doping (additives);Electrolytes;Metal ions;Pyrites;Sodium compounds;Sulfur compounds;Swelling;Chemical-bath deposition;Experimental analysis;Intrinsic electronics;Rate capabilities;Sluggish kinetics;Sulfidation treatment;Theoretical calculations;Theoretical capacity;Sodium-ion batteries
摘要：
Nanostructured iron sulfides are regarded as a potential anode material for sodium-ion batteries in virtue of the rich natural abundance and remarkable theoretical capacity. However, poor rate performance and inferior cycling stability caused by sluggish kinetics and volume swelling represent two main obstacles at present. The previous research mainly focuses on nanostructure design and/or hybridizing with conductive materials. Further boosting the property by adjusting Fe/S atomic ratio in iron sulfides is rarely reported. In this work, Fe7S8 and FeS2 encapsulated in N-doped hollow carbon fibers (NHCFs/Fe7S8 and NHCFs/FeS2) are constructed by a combined chemical bath deposition and subsequent sulfidation treatment. The well-designed NHCFs/Fe7S8 electrode displays a remarkable capacity of 517 mAh g−1 at 2 A g−1 after 1000 cycles and a superb rate capability with a capability of 444 mAh g−1 even at 20 A g−1 in ether-based electrolyte. Additionally, the rate capability of NHCFs/Fe7S8 is superior to that of the contrast NHCFs/FeS2 electrode and also much better than the values of the most previously reported iron sulfide-based anodes. The in-depth mechanism explanation is explained by further experimental analysis and theoretical calculation, revealing Fe7S8 displays improved intrinsic electronic conductivity and faster Na+ diffusion coefficient as well as higher reaction reversibility. © 2020 Science Press
语种：
英文
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The exceptionally high thermal conductivity after 'alloying' two-dimensional gallium nitride (GaN) and aluminum nitride (AlN)
作者：
Wang, Huimin;Wei, Donghai;Duan, Junfei;Qin, Zhenzhen;Qin, Guangzhao* ;...
期刊：
Nanotechnology ,2021年32(13):135401 ISSN：0957-4484
通讯作者：
Yao, Yagang;Hu, Ming;Qin, Guangzhao
作者机构：
[Wang, Huimin; Yao, Yagang] Nanjing Univ, Jiangsu Key Lab Artificial Funct Mat, Coll Engn & Appl Sci, Natl Lab Solid State Microstruct, Nanjing 210093, Peoples R China.;[Wang, Huimin; Yao, Yagang] Nanjing Univ, Collaborat Innovat Ctr Adv Microstruct, Nanjing 210093, Peoples R China.;[Wang, Huimin; Hu, Ming] Univ South Carolina, Dept Mech Engn, Columbia, SC 29208 USA.;[Wang, Huimin; Qin, Guangzhao; Wei, Donghai] Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China.;[Wei, Donghai; Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.
通讯机构：
[Yao, Yagang] N;[Hu, Ming] U;[Qin, Guangzhao] H;[Yao, Yagang] C;Nanjing Univ, Jiangsu Key Lab Artificial Funct Mat, Coll Engn & Appl Sci, Natl Lab Solid State Microstruct, Nanjing 210093, Peoples R China.
关键词：
Alloying;Aluminum alloys;Aluminum nitride;Boltzmann equation;Calculations;Conversion efficiency;Gallium nitride;III-V semiconductors;Knowledge management;Nitrides;Phase space methods;Thermal conductivity of solids;Thermoelectric energy conversion;Aluminum nitride (AlN);Boltzmann transport equation;Electron localization function;First-principles calculation;Gallium nitrides (GaN);High thermal conductivity;Thermal transport properties;Thermoelectric devices;Gallium alloys
摘要：
Alloying is a widely employed approach for tuning properties of materials, especially for thermal conductivity which plays a key role in the working liability of electronic devices and the energy conversion efficiency of thermoelectric devices. Commonly, the thermal conductivity of an alloy is acknowledged to be the smallest compared to the parent materials. However, the findings in this study bring some different points of view on the modulation of thermal transport by alloying. The thermal transport properties of monolayer GaN, AlN, and their alloys of GaxAl1−xN are comparatively investigated by solving the Boltzmann transport equation (BTE) based on first-principles calculations. The thermal conductivity of Ga0.25Al0.75N alloy (29.57 Wm−1 K−1) and Ga0.5Al0.5N alloy (21.49 Wm−1 K−1) are found exceptionally high to be between AlN (74.42 Wm−1 K−1) and GaN (14.92 Wm−1 K−1), which violates the traditional knowledge that alloying usually lowers thermal conductivity. The mechanism resides in that, the existence of Al atoms reduces the difference in atomic radius and masses of the Ga0.25Al0.75N alloy, which also induces an isolated optical phonon branch around 18 THz. As a result, the scattering phase space of Ga0.25Al0.75N is largely suppressed compared to GaN. The microscopic analysis from the orbital projected electronic density of states and the electron localization function further provides insight that the alloying process weakens the polarization of bonding in Ga0.25Al0.75N alloy and leads to the increased thermal conductivity. The exceptionally high thermal conductivity of the GaxAl1−xN alloys and the underlying mechanism as revealed in this study would bring valuable insight for the future research of materials with applications in high-performance thermal management. © 2021 IOP Publishing Ltd.
语种：
英文
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Effects of chelating agents on electrochemical properties of Na0.9Ni0.45Mn0.55O2 cathode materials
作者：
Liu, Zengsheng;Li, Lingjun* ;Chen, Jie;Yang, Huiping;Xia, Lingfeng;...
期刊：
Journal of Alloys and Compounds ,2021年855:157485 ISSN：0925-8388
通讯作者：
Li, Lingjun
作者机构：
[Chen, Jiaxin; Yang, Huiping; Xia, Lingfeng; Chen, Zhaoyong; Liu, Zengsheng; Chen, Jie; Li, Lingjun; Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.;[Li, Lingjun] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410004, Peoples R China.
通讯机构：
[Li, Lingjun] C;Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.
关键词：
Amines;Cathode materials;Chelation;Citric acid;Electrochemical properties;Ethylene;Ethylenediaminetetraacetic acid;Manganese compounds;Metal ions;Nickel compounds;Sodium compounds;Sodium-ion batteries;Sol-gel process;Sol-gels;Complexing agents;Cycled electrode;Electrochemical performance;Interfacial stabilities;Layered cathode;Layered cathode materials;Molecular levels;Selection criteria;Cathodes
摘要：
The development of the layered cathode material for sodium ion batteries are hindered by synthesis approaches. The sol-gel method is a promising way to prepare the cathodes due to the advantage of mixing the raw product at atomic or molecular level, while the selection criteria for complexing agents are still unclear. Herein, the Na0.9Ni0.45Mn0.55O2 cathode is successfully prepared via sol-gel method, by using sucrose, glucose, citric acid, and ethylene diamine tetra-acetic acid as the chelating agent, respectively. The effects of different chelating agents on the morphologies, structural and electrochemical properties are studied in detail. Electrochemical properties prove that the sample using citric acid shows the best electrochemical performance, delivering a capacity of 96 mAh g(-1) and 48% retention after 300 cycles at 1C, and 59.6 mAh g(-1) of capacity at 10 C rate, which are significantly higher than those of the other samples. XRD and HRTEM are conducted for the cycled electrodes, which demonstrate that the structure of the optimized sample maintains better phase stability and interfacial stability. This work is of considerable significance in understanding the selection criteria for the synthesis of layered cathode chelators for sodium-ion batteries by the sol-gel method. (C) 2020 Elsevier B.V. All rights reserved.
语种：
英文
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Template-Free Synthesis of N-Doped Porous Carbon Materials From Furfuryl Amine-Based Protic Salts
作者：
Zhang, Yan* ;Wang, Jixia;Shen, Guohong;Duan, Junfei;Zhang, Shiguo
期刊：
FRONTIERS IN CHEMISTRY ,2020年8:506908 ISSN：2296-2646
通讯作者：
Zhang, Yan
作者机构：
[Wang, Jixia; Shen, Guohong; Zhang, Yan; Zhang, Shiguo] Hunan Univ, Hunan Prov Key Lab Adv Carbon Mat & Appl Technol, Coll Mat Sci & Engn, Changsha, Peoples R China.;[Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha, Peoples R China.
通讯机构：
[Zhang, Yan] H;Hunan Univ, Hunan Prov Key Lab Adv Carbon Mat & Appl Technol, Coll Mat Sci & Engn, Changsha, Peoples R China.
关键词：
Template-free;Nitrogen-doped porous carbon;Furfuryl amine;protic salts;Anions
摘要：
Nitrogen-doped porous carbon materials (NPCMs) are usually obtained by carbonization of complicated nitrogen-containing polymers in the presence of template or physical/chemical activation of the as-synthesized carbon materials. Herein we reported the facile synthesis of NPCMs by direct carbonization of a series of furfuryl amine (FA)-based protic salts ([FA][X], X = NTf2, HSO4, H2PO4, CF3SO3, BF4, NO3, Cl) without any templates, tedious synthetic steps and other advanced techniques. The thermal decomposition of precursors and structure, elemental composition, surface atomic configuration, and porosity of carbons have been carefully investigated by thermogravimetric analysis (TGA), X-ray diffraction (XRD), Raman spectra, X-ray photoelectron spectroscopy (XPS), combustion elemental analysis, energy-dispersive spectrometry, and nitrogen isotherm adsorption. Different from the parent amine FA that was evaporated below 130°C and no carbon was finally obtained, it was found that all the prepared protic precursors yield NPCMs. These carbon materials were found to exhibit anion structure- dependent carbon yield, chemical composition, and porous structure. The obtained NPCMs can be further exploited as adsorbents for dye removal and decoloration. Among all NPCMs, [FA][H2PO4]-derived carbon owing to its high surface area and special pore structure exhibits the highest adsorption capacities toward both Methylene blue and Rhodamine B. © Copyright © 2020 Zhang, Wang, Shen, Duan and Zhang.
语种：
英文
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Solid-state synthesis of lanthanum-based oxides Co-coated LiNi0.5Co0.2Mn0.3O2 for advanced lithium ion batteries
作者：
Li, Lingjun* ;Xia, Lingfeng;Yang, Huiping;Zhan, Xuehui* ;Chen, Jie;...
期刊：
Journal of Alloys and Compounds ,2020年832:154959 ISSN：0925-8388
通讯作者：
Li, Lingjun;Zhan, Xuehui
作者机构：
[Yang, Huiping; Xia, Lingfeng; Chen, Zhaoyong; Zhan, Xuehui; Chen, Jie; Li, Lingjun; Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410114, Peoples R China.
通讯机构：
[Li, LJ; Zhan, XH] C;Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410114, Peoples R China.
关键词：
Cathodes;Coatings;Cobalt compounds;Lanthanum compounds;Lithium compounds;Manganese compounds;Nickel compounds;Solid-State Batteries;Advanced lithium-ion batteries;Electrochemical test;Electron transportation;High voltage applications;Interface stabilities;Solid state approach;Solid-state synthesis;Synthesis procedure;Lithium-ion batteries
摘要：
The high voltage application of the LiNi0.5Co0.2Mn0.3O2 cathode is still hindered by its unstable surficial structure and poor capacity retention. Surface coating has been proved to be an effective strategy to deal with these problems. However, previous multistep surface coating approaches greatly complicate the synthesis procedure. In this work, a simple and large-scale solid-state approach is developed to prepare lanthanum-based oxides co-coated LiNi0.5Co0.2Mn0.3O2 cathode materials. Electrochemical tests indicate that the co-coated samples exhibit superior cycle life and higher rate performance than those of the pristine sample. Further studies reveal that the enhanced interface stability and facilitated electron transportation can be attributed to the synergetic contribution provided by the lanthanum-based oxides co-coating layer. The present work demonstrates that our approach can achieve cathode synthesis and surface coating synchronously, and shows great potential to apply on a large scale and extent to all Ni-rich cathodes. © 2020 Elsevier B.V.
语种：
英文
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Constructing a 3D compact sulfur host based on carbon-nanotube threaded defective Prussian blue nanocrystals for high performance lithium-sulfur batteries
作者：
Shen, Guohong;Liu, Zhixiao;Liu, Piao;Duan, Junfei;Younus, Hussein A.;...
期刊：
Journal of Materials Chemistry A ,2020年8(3):1154-1163 ISSN：2050-7488
通讯作者：
Wang, Xiwen;Zhang, Shiguo
作者机构：
[Liu, Zhixiao; Shen, Guohong; Wang, Xiwen; Zhang, Shiguo; Younus, Hussein A.] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China.;[Liu, Piao] Hunan LEED Elect Ink Co Ltd, Zhuzhou 412007, Hunan, Peoples R China.;[Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.;[Deng, Huiqiu] Hunan Univ, Sch Phys & Elect, Changsha 410082, Hunan, Peoples R China.;[Younus, Hussein A.] Fayoum Univ, Dept Chem, Fac Sci, Al Fayyum 63514, Egypt.
通讯机构：
[Wang, XW; Zhang, SG] H;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China.
会议名称：
10th International Conference on Materials for Advanced Technologies (ICMAT) / Symposium P on Advanced Inorganic Materials and Thin Film Technology for Solar Energy Harvesting and Electronic Application
会议时间：
JUN 23-28, 2019
会议地点：
Mat Res Soc Singapore, Singapore, SINGAPORE
会议主办单位：
Mat Res Soc Singapore
摘要：
Towards practical lithium-sulfur batteries, the rational design of a sulfur host that enables highly efficient sulfur electrochemistry and high areal sulfur loading is essential but still a challenge. Here, a class of 3D nanocomposite architecture characterised by a necklace-like structure that contains intertwined carbon-nanotubes (CNTs) and defective Prussian blue (PB) nanocrystals is developed as the sulfur host. Benefiting from the fact that a 3D CNT conductive skeleton can provide efficient ion/electron channels and the abundant Lewis acidic sites in PB can effectively entrap lithium polysulfide (LiPS) species, the S@PB/CNT composite cathode exhibits high reversibility, stable cycling performance, and fast kinetics. More importantly, the LiPS adsorption capacity of PB materials and the kinetics of LiPS conversion on PB is highly dependent on the amount of [Fe(CN)6] vacancies based on both theoretical and experimental studies, which may further shed light on the interfacial phenomena between the PB sulfur host and soluble LiPS in the electrolyte. © 2019 The Royal Society of Chemistry.
语种：
英文
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New Insight into the Confinement Effect of Microporous Carbon in Li/Se Battery Chemistry: A Cathode with Enhanced Conductivity
作者：
Wang, Xiwen;Tan, Yuqing;Liu, Zhixiao;Fan, Yuqin;Li, Mingnan;...
期刊：
Small ,2020年16(17):2000266- ISSN：1613-6810
通讯作者：
Zhang, Shiguo
作者机构：
[Liu, Zhixiao; Tan, Yuqing; Wang, Xiwen; Fan, Yuqin; Li, Mingnan; Younus, Hussein A.; Zhang, Shiguo] Hunan Univ, Coll Mat Sci & Engn, State Key Lab Adv Design & Mfg Vehicle Body, Tianma Rd 27, Changsha 410082, Hunan, Peoples R China.;[Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.;[Deng, Huiqiu] Hunan Univ, Sch Phys & Elect, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Zhang, Shiguo] H;Hunan Univ, Coll Mat Sci & Engn, State Key Lab Adv Design & Mfg Vehicle Body, Tianma Rd 27, Changsha 410082, Hunan, Peoples R China.
关键词：
conductivity;confined Se cathodes;electrolytes;lithium-selenium batteries
摘要：
Embedding the fragmented selenium into the micropores of carbon host has been regarded as an effective strategy to change the Li–Se chemistry by a solid–solid mechanism, thereby enabling an excellent cycling stability in Li–Se batteries using carbonate electrolyte. However, the effect of spatial confinement by micropores in the electrochemical behavior of carbon/selenium materials remains ambiguous. A comparative study of using both microporous (MiC) and mesoporous carbons (MeC) with narrow pore size distribution as selenium hosts is herein reported. Systematic investigations reveal that the high Se utilization rate and better electrode kinetics of MiC/Se cathode than MeC/Se cathode may originate from both its improved Li+ and electronic conductivities. The small pore size ('1.35 nm) of the carbon matrices not only facilitates the formation of a compact and robust solid-electrolyte interface (SEI) with low interfacial resistance on cathode, but also alters the insulating nature of Li2Se due to the emergence of itinerant electrons. By comparing the electrochemical behavior of MiC/Se cathode and the matching relationship between the diameter of pores and the dimension of solvent molecules in carbonate, ether, and solvate ionic liquid electrolyte, the key role of SEI film in the operation of C/Se cathode by quasi-solid-solid mechanism is also highlighted. © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
语种：
英文
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“三全育人”格局下高校研究生创新精神的提升策略
作者：
李灵均;王微;蒋琳嫒;段军飞
期刊：
科教导刊 ,2020年(27):5-6 ISSN：1674-6813
作者机构：
长沙理工大学材料科学与工程学院 湖南·长沙 410114;长沙理工大学物理与电子科学学院 湖南·长沙 410114;[王微; 李灵均; 蒋琳嫒; 段军飞] 长沙理工大学
关键词：
三全育人;研究生;创新精神;三建三改
摘要：
研究生教育处于国民教育体系顶端,其创新能力关系着高校服务社会能力,关系着国家创新驱动发展战略。本文立足"三全育人",依托导师团队建设、联合支部建设、课程思政教育、高水平成果评价和导向机制建设的"三建三改"提升策略,开展研究生创新精神的探索与实践研究,为有效增强高校研究生的理想信念和创新能力提供新蹊径,同时对提高高校研究生培养质量以及建设高水平大学及重点学科具有重要的理论意义。
语种：
中文
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Engineering red phosphorus confined in TiO2-coated ultrathin carbon-bubble foam with enhanced Li+ storage capability
作者：
Wei, Donghai;Wu, Yinglong;Nie, Yan;Duan, Junfei* ;Cao, Chenhao;...
期刊：
Applied Surface Science ,2020年529:147114 ISSN：0169-4332
通讯作者：
Duan, Junfei;Zhang, Guanhua
作者机构：
[Cao, Chenhao; Chen, Zhaoyong; Wu, Yinglong; Wei, Donghai; Duan, Junfei; Li, Lingjun] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Hunan Prov Key Lab Mat Protect Elect Power & Tran, Changsha 410004, Peoples R China.;[Zhang, Guanhua; Duan, Huigao; Nie, Yan] Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[Wu, Jianghong] Shenzhen Technol Univ, Coll Hlth Sci & Environm Engn, Shenzhen 518118, Guangdong, Peoples R China.
通讯机构：
[Duan, Junfei] C;[Zhang, Guanhua] H;Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Hunan Prov Key Lab Mat Protect Elect Power & Tran, Changsha 410004, Peoples R China.;Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词：
Anode;Lithium ion battery;Low-temperature atomic layer deposition;Red phosphorus;Ultrathin porous carbon;Vaporization-condensation
摘要：
Red phosphorus (RP), as one of the most promising anode materials for lithium-ion batteries, attracts much attention for its high theoretical specific capacity, cost-effective, and commercial availability. However, poor cycling stability and rate capability caused by huge volume expansion and low intrinsic electronic conductivity hinder the commercialization of RP-based anode. Herein, RP confined in ultrathin hollow carbon-bubble-constructed foam (RP-HC) is developed to improve electronic conductivity and mechanical structure stability. Additionally, low-temperature atomic layer deposition (LT-ALD) technology is adopted to further modify the surface of the RP-HC, forming a core–shell RP-HC@TiO2 structure with about 5 nm TiO2 coating layer. Benefiting from the dual confinement of TiO2 buffer layer and conductive porous carbon host with effective P–O–C bond, the RP-HC(70%)@TiO2 electrode delivers an outstanding cycling performance (795.2 mAh g−1 after 200 cycles at 100 mA g−1) and rate capability (459.9 mAh g−1 at 2000 mA g−1, almost 1.6 times and 12 times relative to RP-HC(70%) and RP under the same test condition). In-situ electrochemical impedance spectroscopy analyses are also conducted to investigate the superior Li+ storage properties of the RP-HC@TiO2. © 2020 Elsevier B.V.
语种：
英文
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Free-standing phosphorous-doped molybdenum nitride in 3D carbon nanosheet towards hydrogen evolution at all pH values
作者：
Wang, Qiyou;Zhang, Yan;Ni, Wenpeng;Zhang, Yi;Sun, Tian;...
期刊：
能源化学(英文) ,2020年50(11):44-51 ISSN：2095-4956
通讯作者：
Gao, Yang;Zhang, Shiguo
作者机构：
[Wang, Qiyou; Sun, Tian; Gao, Yang; Zhang, Yi; Zhang, Yan; Zhang, Shiguo; Ni, Wenpeng] Hunan Univ, Coll Mat Sci & Engn, Hunan Prov Key Lab Adv Carbon Mat & Appl Technol, Changsha 410082, Hunan, Peoples R China.;[Zhang, Jiaheng] Harbin Inst Technol, Sch Mat Sci & Engn, Shenzhen 518055, Guangdong, Peoples R China.;[Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Hunan, Peoples R China.
通讯机构：
[Gao, Y; Zhang, SG] H;Hunan Univ, Coll Mat Sci & Engn, Hunan Prov Key Lab Adv Carbon Mat & Appl Technol, Changsha 410082, Hunan, Peoples R China.
关键词：
Hydrogen evolution reaction;Molybdenum nitride;Heteroatoms doping;Free-standing catalyst;DFT calculations
摘要：
Highly efficient electrocatalysts towards hydrogen evolution reaction (HER) with large current density at all-pH values are critical for the sustainable hydrogen production. Herein, we report a free-standing HER electrode, phosphorous-doped molybdenum nitride nanoparticles embedded in 3-dimentional carbon nanosheet matrix (P-Mo2N-CNS) fabricated via one-step carbonization and in-situ formation. The as-prepared catalyst shows free-standing architecture with interconnected porous microstructure. P-doped Mo2N nanoparticles with an average diameter of 4.4 nm are well embedded in the 3-dimentional vertical carbon nanosheets matrix. Remarkable electrocatalytic HER performance is observed in alkaline, neutral and acidic media at large current densities. The overpotential of P-Mo2N-CNS to drive a current density of 100 mA cm−2 in 0.5 M H2SO4 and 1.0 M PBS is only 181 and 221 mV, respectively. In particular, the current density reaches up to 1000 mA cm−2 at a low overpotential of 256 mV in 1.0 M KOH, much better than that of the commercial Pt/C catalyst. Density functional theory calculations suggest the optimized H sorption kinetics on Mo2N after P doping, elucidating the superior activity. © 2020
语种：
英文
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Bimetal-organic Framework-derived Co9S8/ZnS@NC Heterostructures for Superior Lithium-ion Storage
作者：
Duan, Junfei;Wang, Yongkang;Li, Hongxing* ;Wei, Donghai;Wen, Fang;...
期刊：
CHEMISTRY-AN ASIAN JOURNAL ,2020年15(10):1613-1620 ISSN：1861-4728
通讯作者：
Chen, Zhaoyong;Li, Hongxing;Zhang, Guanhua
作者机构：
[Chen, Zhaoyong; Wen, Fang; Wei, Donghai; Duan, Junfei; Li, Lingjun; Wang, Yongkang] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.;[Li, Hongxing; Zhang, Wei-bing] Changsha Univ Sci & Technol, Sch Elect Sci & Technol, Changsha 410004, Peoples R China.;[Zhang, Guanhua] Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Bod, Changsha 410004, Peoples R China.;[Liu, Piao] Hunan LEED Elect Ink Co Ltd, Inst Zhuzhou, Zhuzhou, Hunan, Peoples R China.
通讯机构：
[Chen, Zhaoyong; Li, Hongxing] C;[Zhang, Guanhua] H;Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.;Changsha Univ Sci & Technol, Sch Elect Sci & Technol, Changsha 410004, Peoples R China.;Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Bod, Changsha 410004, Peoples R China.
关键词：
heterostructure;internal electric field;vapor chemical transformation;metal sulfides;anode;lithium ion battery
摘要：
<jats:title>Abstract</jats:title><jats:p>Heterostructure engineering of electrode materials, which is expected to accelerate the ion/electron transport rates driven by a built‐in internal electric field at the heterointerface, offers unprecedented promise in improving their cycling stability and rate performance. Herein, carbon nanotubes with Co<jats:sub>9</jats:sub>S<jats:sub>8</jats:sub>/ZnS heterostructures embedded in a N‐doped carbon framework (Co<jats:sub>9</jats:sub>S<jats:sub>8</jats:sub>/ZnS@NC) have been rationally designed via an in‐situ vapor chemical transformation strategy with the aid of thiophene, which not only acted as carbon source for the growth of carbon nanotubes but also as sulfur source for the sulfurization of metal Zn and Co. Density functional theory (DFT) calculation shows an about 3.24 eV electrostatic potential difference between ZnS and Co<jats:sub>9</jats:sub>S<jats:sub>8</jats:sub>, which results in a strong electrostatic field across the interface that makes electrons transfer from Co<jats:sub>9</jats:sub>S<jats:sub>8</jats:sub> to the ZnS side. As expected, a stable cycling performance with reversible capacity of 411.2 mAh g<jats:sup>−1</jats:sup> at 1000 mA g<jats:sup>−1</jats:sup> after 300 cycles, excellent rate capability (324 mAh g<jats:sup>−1</jats:sup> at 2000 A g<jats:sup>−1</jats:sup>) and a high percentage of pseudocapacitance contribution (87.5% at 2.2 mv/s) for lithium‐ion batteries (LIBs) are achieved. This work provides a possible strategy for designing multicomponent heterostructural materials for application in energy storage and conversion fields.</jats:p>
语种：
英文
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Fe3O4 nanoparticles encapsulated in single-atom Fe–N–C towards efficient oxygen reduction reaction: Effect of the micro and macro pores
作者：
Hu, Shuqi;Ni, Wenpeng;Yang, Daihui;Ma, Chao;Zhang, Jiaheng;...
期刊：
Carbon ,2020年162:245-255 ISSN：0008-6223
通讯作者：
Gao, Yang;Zhang, Shiguo
作者机构：
[Ma, Chao; Gao, Yang; Yang, Daihui; Zhang, Shiguo; Hu, Shuqi; Ni, Wenpeng] Hunan Univ, Coll Mat Sci & Engn, Hunan Prov Key Lab Adv Carbon Mat & Appl Technol, Changsha 410082, Hunan, Peoples R China.;[Zhang, Jiaheng] Harbin Inst Technol Shenzhen, Sch Mat Sci & Engn, Pr China 518055, Peoples R China.;[Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.
通讯机构：
[Gao, Y; Zhang, SG] H;Hunan Univ, Coll Mat Sci & Engn, Hunan Prov Key Lab Adv Carbon Mat & Appl Technol, Changsha 410082, Hunan, Peoples R China.
关键词：
Fe3O4 nanoparticles;Macro-pores;Micro-pores;Oxygen reduction reaction;Single atom catalysts
摘要：
Atomically dispersed Fe-N-C catalysts with additional Fe-containing nanoparticles including metal, carbides or oxides have shown great potentials towards oxygen reduction reaction (ORR) catalysis. However, the formation of these synergistically active nanoparticles and the effect of the porous carbon structures remain unclear. In this work, a novel single-atom-involved electrochemical catalyst, i.e., Fe3O4 nanoparticles encapsulated in atomically dispersed Fe-N-C (Fe3O4@FeNC) was reported. The optimized Fe3O4@FeNC exhibits excellent ORR activity with a half-wave potential of 0.890 V and a Tafel slope of 58.8 mV dec(-1), comparable with recently reported ORR catalysts and superior to these of commercial Pt/C. More importantly, the porous architectures not only affect the mass transfer and active sites, but casts huge influence on the nucleation of Fe3O4 nanoparticles, the graphitization degree of the carbon support, the chemical environments of the elements, and the ORR catalytic pathways. Density functional theory calculations show stronger O-2 adsorption on Fe-N-C when supported on Fe3O4 moieties, which may increase the reactant concentration for ORR and promote the overall activity. These findings will provide important references for the future understanding and design of single-atom-involved catalysts with enhanced electrochemical properties. (c) 2020 Elsevier Ltd. All rights reserved.
语种：
英文
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High-performance lithium-rich layered oxide material: Effects of preparation methods on microstructure and electrochemical properties
作者：
Liu, Qiming;Zhu, Huali;Liu, Jun;Liao, Xiongwei;Tang, Zhuolin;...
期刊：
Materials ,2020年13(2):334 ISSN：1996-1944
通讯作者：
Chen, Zhaoyong
作者机构：
[Liu, Qiming; Yuan, Mengming; Chen, Zhaoyong; Liao, Xiongwei; Tang, Zhuolin; Liu, Jun; Zhou, Cankai; Duan, Junfei; Li, Lingjun] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.;[Zhu, Huali] Changsha Univ Sci & Technol, Sch Phys & Elect Sci, Changsha 410114, Peoples R China.
通讯机构：
[Chen, Zhaoyong] C;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.
关键词：
Cathode materials;Cathodes;Coprecipitation;Electric discharges;Ions;Lithium compounds;Oxalic acid;Sol-gel process;Sol-gels;0.5Li2MnO3.0.5LiMn0.8Ni0.1Co0.1O2;Coprecipitation method;Discharge specific capacity;Electrochemical performance;High energy densities;Lithium ion diffusion;Lithium-rich layered oxides;Oxalate co-precipitation method;Lithium-ion batteries
摘要：
Lithium-rich layered oxide is one of the most promising candidates for the next-generation cathode materials of high-energy-density lithium ion batteries because of its high discharge capacity. However, it has the disadvantages of uneven composition, voltage decay, and poor rate capacity, which are closely related to the preparation method. Here, 0.5Li2MnO3-0.5LiMn0.8Ni0.1Co0.1O2 was successfully prepared by sol-gel and oxalate co-precipitation methods. A systematic analysis of the materials shows that the 0.5Li2MnO3.0.5LiMn0.8Ni0.1Co0.1O2 prepared by the oxalic acid co-precipitation method had the most stable layered structure and the best electrochemical performance. The initial discharge specific capacity was 261.6 mAh.g-1 at 0.05 C, and the discharge specific capacity was 138 mAh.g-1 at 5 C. The voltage decay was only 210 mV, and the capacity retention was 94.2% after 100 cycles at 1 C. The suppression of voltage decay can be attributed to the high nickel content and uniform element distribution. In addition, tightly packed porous spheres help to reduce lithium ion diffusion energy and improve the stability of the layered structure, thereby improving cycle stability and rate capacity. This conclusion provides a reference for designing high-energy-density lithium-ion batteries. © 2020 by the authors.
语种：
英文
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Submicron-sized Nb-doped lithium garnet for high ionic conductivity solid electrolyte and performance of quasi-solid-state lithium battery
作者：
Ji, Yan;Zhou, Cankai;Lin, Feng;Li, Bingjing;Yang, Feifan;...
期刊：
Materials ,2020年13(3):560 ISSN：1996-1944
通讯作者：
Chen, Zhaoyong
作者机构：
[Ji, Yan; Chen, Zhaoyong; Li, Bingjing; Zhou, Cankai; Lin, Feng; Yang, Feifan; Duan, Junfei] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.;[Zhu, Huali] Changsha Univ Sci & Technol, Coll Phys & Elect Sci, Changsha 410114, Peoples R China.
通讯机构：
[Chen, Zhaoyong] C;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.
关键词：
Activation energy;Chemical stability;Electric discharges;Electrochemical impedance spectroscopy;Garnets;Ionic conduction in solids;Ionic conductivity;Lanthanum compounds;Lithium compounds;Lithium-ion batteries;Manganese compounds;Milling (machining);Niobium compounds;Particle size;Particle size analysis;Phase structure;Powder metals;Scanning electron microscopy;Sintering;Solid state devices;Solid state reactions;Solid-State Batteries;Temperature;Zirconium compounds;Discharge specific capacity;Distribution of element;Electrochemical window;High sintering temperatures;High-temperature sintering;Lithium-ion conductivity;Solid-state electrolyte;Submicron powders;Solid electrolytes
摘要：
The garnet Li7La3Zr2O12 (LLZO) has been widely investigated because of its high conductivity, wide electrochemical window, and chemical stability with regards to lithium metal. However, the usual preparation process of LLZO requires high-temperature sintering for a long time and a lot of mother powder to compensate for lithium evaporation. In this study submicron Li6.6La3Zr1.6Nb0.4O12 (LLZNO) powder-which has a stable cubic phase and high sintering activity-was prepared using the conventional solid-state reaction and the attrition milling process, and Li stoichiometric LLZNO ceramics were obtained by sintering this powder-which is difficult to control under high sintering temperatures and when sintered for a long time-at a relatively low temperature or for a short amount of time. The particle-size distribution, phase structure, microstructure, distribution of elements, total ionic conductivity, relative density, and activation energy of the submicron LLZNO powder and the LLZNO ceramics were tested and analyzed using laser diffraction particle-size analyzer (LD), X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Electrochemical Impedance Spectroscopy (EIS), and the Archimedean method. The total ionic conductivity of samples sintered at 1200 °C for 30 min was 5.09 × 10-4 S cm-1, the activation energy was 0.311 eV, and the relative density was 87.3%. When the samples were sintered at 1150 °C for 60 min the total ionic conductivity was 3.49 × 10-4 S cm-1, the activation energy was 0.316 eV, and the relative density was 90.4%. At the same time, quasi-solid-state batteries were assembled with LiMn2O4 as the positive electrode and submicron LLZNO powder as the solid-state electrolyte. After 50 cycles, the discharge specific capacity was 105.5 mAh/g and the columbic efficiency was above 95%. © 2020 by the authors.
语种：
英文
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Cobalt phthalocyanine derived bifunctional carbon decorated CoSe with enhanced lithium storage capability
作者：
Wu, Yinglong;Cao, Chenhao;Xu, Jiaxiong;Wei, Donghai;Duan, Junfei* ;...
期刊：
Synthetic Metals ,2020年269:116554 ISSN：0379-6779
通讯作者：
Duan, Junfei
作者机构：
[Cao, Chenhao; Chen, Zhaoyong; Wu, Yinglong; Wei, Donghai; Xu, Jiaxiong; Duan, Junfei; Li, Lingjun] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.;[Wu, Jianghong] Shenzhen Technol Univ, Coll Hlth Sci & Environm Engn, Shenzhen 518118, Guangdong, Peoples R China.
通讯机构：
[Duan, Junfei] C;Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.
关键词：
CoSe;bifunctional carbon;Ethanol Steam Reforming;catalytic activity;synergistic effect
摘要：
Transition-metal chalcogenides (TMCs) have attracted much attention as their good electrical conductivity and high lithium storage capacity. In this work, a simple and scalable approach was employed to synthesize CoSe nanoparticles confined in bifunctional N-doped carbon framework/carbon layer (CoSe/NC/C). Specifically, pyrolysis of cobalt phthalocyanine (CoPc)/Selenium mixtures was accompanied by Ethanol Steam Reforming (ESR) simultaneously, which could bring in double carbon network and restrict the growth of CoSe grains effectively to achieve more stable structure and fast ion/electron transfer within CoSe electrode. As a result, CoSe/NC/C composite delivers a superior discharge capacity of 531 mA h g-1 after 400 cycles at 1 A g-1 at room temperature and a remarkable cycling stability (458 mA h g-1 after 100 cycles at 1 A g-1) at elevated temperature (55 ℃). This excellent electrochemical performance may be attributed to the following factors. (a) The bifunctional carbon architecture can not only endow the composites with superior conductivity and enhanced structure stability, but also facilitate the uniform distribution of nano-sized CoSe. (b) The effective catalytic activity is inspired by the synergistic effect between CoSe nanoparticles and bifunctional carbon, which is supposed to contribute significant capacity and manifest distinct pseudocapacitive behavior, especially at high current density. © 2020 Elsevier B.V.
语种：
英文
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Simultaneous synthesis and synergetic stabilization of Zr-doped and Li6Zr2O7-coated Ni-rich layered cathode for advanced lithium ion batteries
作者：
Yang, Huiping;Li, Lingjun* ;Liu, Chaoyang;Chen, Jie;Xia, Lingfeng;...
期刊：
Electrochimica Acta ,2020年364:137120 ISSN：0013-4686
通讯作者：
Li, Lingjun
作者机构：
[Chen, Jiaxin; Yang, Huiping; Xia, Lingfeng; Chen, Zhaoyong; Liu, Chaoyang; Liu, Zengsheng; Chen, Jie; Li, Lingjun; Duan, Junfei] Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.
通讯机构：
[Li, Lingjun] C;Changsha Univ Sci & Technol, Sch Mat Sci & Engn, Changsha 410004, Peoples R China.
关键词：
Nickel-rich cathode materials;Zr-doping;Li6Zr2O7-coating;Interfacial stability;Bulk stability
摘要：
Ni-rich cathode materials, one of the most promising cathodes for high-energy lithium-ion batteries, are still suffered from interfacial instability and bulk degradation. Herein, Zr-doped and Li6Zr2O7-coated LiNi0.8Co0.1Mn0.1O2 cathode, and Zr-doped Li6Zr2O7-LiNi0.8Co0.1Mn0.1O2 composite are successfully pre-pared via a smart one-step calcination process. The attained dual-modified architecture allows the optimized sample exhibiting enhanced rate performance while maintaining long-term stability at room temperature (82.13% after 200 cycles at 1 C rate) and even at elevated temperature. Further studies reveal that the delayed temperature-driven phase transition and the suppressed interfacial degradation can be addressed with the synergetic effects provided by the Zr-doping and Li6Zr2O7-coating. The Zr doping could improve bulk stability by reducing cation disorder. The conductive Li6Zr2O7 surface coating enhances the interfacial stability of the cathode materials while improving the electrochemical kinetics. This smart modification strategy renders Zr modification a viable modification method to enhance the electrochemical performance and structural properties of Ni-rich cathode materials. (C) 2020 Published by Elsevier Ltd.
语种：
英文
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Effect of Different Composition on Voltage Attenuation of Li-Rich Cathode Material for Lithium-Ion Batteries.
作者：
Liu, Jun;Liu, Qiming;Zhu, Huali;Lin, Feng;Ji, Yan;...
期刊：
Materials ,2019年13(1):40 ISSN：1996-1944
通讯作者：
Chen, Zhaoyong
作者机构：
[Liu, Qiming; Ji, Yan; Chen, Zhaoyong; Li, Bingjing; Liu, Jun; Lin, Feng; Duan, Junfei; Li, Lingjun] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.;[Zhu, Huali] Changsha Univ Sci & Technol, Coll Phys & Elect Sci, Changsha 410114, Peoples R China.
通讯机构：
[Chen, Zhaoyong] C;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Peoples R China.
关键词：
Cathode materials;Cathodes;Cobalt compounds;High resolution transmission electron microscopy;Ions;Lithium-ion batteries;Manganese compounds;Nickel;Nickel compounds;Scanning electron microscopy;Solid-State Batteries;Capacity retention;Commercial applications;Environmental friendliness;Layered oxide cathodes;Layered oxides;Operating voltage;Specific capacities;Specific energy;Lithium compounds
摘要：
Li-rich layered oxide cathode materials have become one of the most promising cathode materials for high specific energy lithium-ion batteries owning to its high theoretical specific capacity, low cost, high operating voltage and environmental friendliness. Yet they suffer from severe capacity and voltage attenuation during prolong cycling, which blocks their commercial application. To clarify these causes, we synthesize Li1.5Mn0.55Ni0.4Co0.05O2.5 (Li1.2Mn0.44Ni0.32Co0.04O2) with high-nickel-content cathode material by a solid-sate complexation method, and it manifests a lot slower capacity and voltage attenuation during prolong cycling compared to Li1.5Mn0.66Ni0.17Co0.17O2.5 (Li1.2Mn0.54Ni0.13Co0.13O2) and Li1.5Mn0.65Ni0.25Co0.1O2.5 (Li1.2Mn0.52Ni0.2Co0.08O2) cathode materials. The capacity retention at 1 C after 100 cycles reaches to 87.5% and the voltage attenuation after 100 cycles is only 0.460 V. Combining X-ray di_raction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM), it indicates that increasing the nickel content not only stabilizes the structure but also alleviates the attenuation of capacity and voltage. Therefore, it provides a new idea for designing of Li-rich layered oxide cathode materials that suppress voltage and capacity attenuation. © 2019 by the authors.
语种：
英文
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新能源材料与器件专业本科生就业分析
作者：
李灵均;陈召勇;段军飞;宋刘斌;朱华丽
期刊：
科技资讯 ,2018年16(16):174-175 ISSN：1672-3791
作者机构：
长沙理工大学材料科学与工程学院 湖南长沙 410114;[陈召勇; 李灵均; 宋刘斌; 朱华丽; 段军飞] 长沙理工大学
关键词：
新能源材料与器件;大学生就业;人力资源
摘要：
为满足新能源开发与利用这一迫切需求,国家于2011年特别设立"新能源材料与器件"专业。本报告选取了三所不同类型、不同地域、具有不同行业背景且开办新能源材料与器件专业较早的高校,通过调研取得了这三所高校新能源材料与器件专业毕业生就业状况的一手资料,数据分析表明我国新能源材料与器件人才供不应求的局面将长期存在。
语种：
中文
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《材料学概论》课程教学探索与实践
作者：
段军飞
期刊：
教育教学论坛 ,2017年(23):151-152 ISSN：1674-9324
作者机构：
长沙理工大学 材料科学与工程学院,湖南 长沙,410114;[段军飞] 长沙理工大学
关键词：
材料学;教学内容;教学模式;课程考核
摘要：
《材料学概论》是我校材料科学与工程学院无机非金属材料专业开设的入门基础课.结合这门课程的特点、教学目的和学生后续深层次专业课程的学习需要,我们从教学内容、教学模式、课程考核等方面进行了课程教学的初步探索与实践,同时总结了课程教学中还需改进的地方.
语种：
中文
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论研究性教学在材料学概论课程中的必要性
作者：
段军飞
期刊：
教育教学论坛 ,2017年(26):194-195 ISSN：1674-9324
作者机构：
长沙理工大学 材料科学与工程学院,长沙,410114;[段军飞] 长沙理工大学
关键词：
研究性教学;材料学概论;可行性;创新性
摘要：
研究性教学是促进教学和科研相结合，培养具有创造性思维和实践能力人才的重要途径，是目前大学课堂教学中的常用模式之一。《材料学概论》课程的内容特别是新兴功能材料更新很快，有很多前沿的科学进展，需要传授给学生并引导他们进行思考和研究，将研究性教学模式引入到《材料学概论》课程教学中，对于提高学生学习主观能动性，培养其科研素养和创新性具有重要借鉴作用。
语种：
中文
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