原位合成壳聚糖复合炭材料及其在铅碳电池中的应用

以壳聚糖、氧化铅为原料,利用原位合成方法,制备复合炭材料。通过X射线粉末衍射仪、扫描电镜和电子能谱仪、比表面仪、拉曼光谱仪等方法对复合炭材料进行表征,结果表明:壳聚糖为碳源的复合炭材料具有非晶态结构,孔径分布集中在5~10nm,比表面积高达487.4m2/g,适合作为Pb-C电池负极材料使用;将原位合成壳聚糖复合炭材料或者炭黑材料与析氢抑制剂、黏结剂、膨胀剂等电池添加剂混合成涂膏,分别组装成Pb-C模拟电池,利用电化学测量技术和电池性能测试系统评价Pb-C电池电化学性能,结果表明:以原位合成壳聚糖复合炭材料作为负极材料制成的Pb-C电池负极板,比以炭黑为碳源制备的负极材料具有更好的电化学性能,电阻较小,其循环伏安测试的比电容为162.9F/g,首次放电平台更长,最终容量达到108.72mAh/g,壳聚糖为碳源时比容量为理论比容量的98%,且10000次循环几乎没有衰减。     

盐辅助原位制备氮掺杂多孔炭提高储钾容量和循环稳定性

钾离子电池因其较高的能量密度和丰富的钾资源,具有成为大规模储能设备的潜力.但钾离子的半径较大引起的可逆容量低和循环稳定性等问题限制了钾离子电池的实际应用.在本项工作中,我们将前驱体细菌纤维素浸泡在作为造孔剂和掺杂剂的Mg(NO3)2溶液中,经炭化和酸洗处理后,制备出氮掺杂细菌纤维素基炭材料(NBCC).该材料有相互连接...     

纳米硅/炭复合材料的制备及其电化学性能

将纳米Si粉以一定配比分散在石油重油中,在高压反应釜中经过460℃自升压热解反应,再经900℃炭化制备一种锂离子二次电池负极用纳米硅/炭（Si/C）复合材料。考察了纳米Si粉添加量对产物收率、微观结构及电化学性能的影响。结果表明：纳米Si粉的加入有助于提高固体产物的收率;在纳米Si/C复合材料中纳米Si粉均匀地镶嵌于炭基体中;纳米Si粉的晶型在热解反应前后没有发生变化。当纳米Si粉与石油重油质量比为5∶100时制备的纳米Si/C复合电极材料具有498mAh/g的首次可逆比容量和90%的充放电效率。     

用于锂离子电池的石墨烯及其复合负极材料的研究进展

石墨烯复合材料因具有高比表面积、高比容量、优异的导电性、显著的化学稳定性,在锂离子电池领域具有巨大的应用前景。在负极复合材料中,石墨烯不仅可以形成导电网络提升复合材料的导电性能,而且还可以缓冲材料在充放电过程中的体积效应,提高了材料的倍率性能和循环寿命,为设计大容量高稳定性的锂离子电池提供了理论保证。因此制备不同组成和结构的石墨烯复合材料是一个非常有价值的课题。对近年来国内外运用不同方法制备不同组成和结构的石墨烯复合材料的研究结果做了综合评述和展望。     

锂离子电池炭负极材料结构的研究进展

综述了近年来锂离子电池碳负极材料结构的研究情况,着重总结了石墨材料、炭材料以及纳米碳材料结构方面的研究进展.     

低比表面积酚醛树脂硬碳的制备及电化学性能

以酚醛树脂为原料、正戊烷为发泡剂,采用发泡法制备了低比表面积的酚醛树脂硬碳。通过SEM、XRD、FTIR和N_2吸附/脱附等方式表征了不同发泡剂添加量下硬碳材料的表面形貌和结构,以金属锂为对电极制备纽扣半电池并测试了其电化学性能。结果分析表明:正戊烷质量分数为20%的硬碳比表面积为1.62 m~2·g~(-1),平均孔径为6.406 nm,(002)晶面层间距d_(002)为0.394 nm,二维碳层尺寸L_a为1.417 nm,平行层群尺寸L_c为2.602 nm,碳产率为45.05%;在50 m A·g~(-1)的电流密度下,其首次比容量达到318.7 m Ah·g~(-1),首次库伦效率为68.9%,并且表现出良好的循环稳定性能和倍率性能。     

炭负极材料储钠机理的研究进展

随着新能源产业的快速发展,储能市场正在逐步崛起,钠离子电池(SIB)作为一种新兴的低成本储能体系受到了广泛的关注。低成本和稳定的电化学特性是炭材料成为推动钠离子电池产业化的关键负极材料。综述了各类炭材料的结构特征和储钠特性及它们的改性措施,并对炭材料的储钠机理进行了讨论和总结,展望了炭基储钠负极材料的未来发展。     

锂离子电池复合负极材料研究进展

将锂离子电池材料尺寸减小到纳米尺度,可减小充放电过程中Li+迁移距离及电极材料的相对膨胀率,是一种有效提升锂离子电池性能的手段。但是,纳米化也会带来导电率低、表面副反应活性高、团聚倾向大等明显缺点。在负极活性材料中引入导电复合相,可以有效提升材料体系的导电性、储锂容量、倍率特性和循环稳定性,是解决现有技术难题的有效突破口之一。对近年锂离子电池负极材料研究方面的主要成果进行了综述,着重关注几种热点负极材料及其新型微结构的设计、实现与性能优化研究。以可控制备工艺为主线,总结了相关的研究成果。     

一步水热法制备纳米SnO2@C复合材料及其储锂性能研究

以两种糖类化合物(葡萄糖与水溶性淀粉)为碳源,以SnCl₄.5H₂O为锡源用一步水热法制备了SnO₂@C复合物。使用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、N₂吸脱附法和透射电镜(TEM)表征其组成和微观结构,并采用恒电流充放电测试、循环伏安法(CV)和电化学阻抗谱(EIS)表征其作为锂离子电池负极材料的电化学性能。结果表明,糖类前驱体衍生的热解炭和直径为4~5 nm的SnO₂纳米点生成了稳定的复合结构,炭基体的缓冲作用和材料纳米化缓解了SnO₂的体积膨胀效应,使材料的结构稳定性和电化学性能提高。由于葡萄糖热解炭的有序度比淀粉热解炭更高,这组试样具有更好的循环性能和倍率性能,在2 A/g大电流密度下其比容量高于400 mAh/g。     

Osiers-sprout-like heteroatom-doped carbon nanofibers as ultrastable anodes for lithium/sodium ion storage

Nano Research - We report an in situ carbothermic reduction process to prepare osiers-sprout-like heteroatom-doped carbon nanofibers. The dosage of copper salts and a unique annealing process have...     

无黏结剂柔性Si/CNT/纤维素复合阳极及其电化学性能

硅/碳复合材料作为最具潜力的下一代阳极材料,受到广泛关注。为减少硅巨大膨胀所产生的应力,避免硅纳米颗粒的粉化,提高硅基锂离子电池的电化学性能,制备了一种多微孔结构的多壁碳纳米管(MWCNTs)纸,嵌入纳米硅制得Si/MWCNTs/纤维素复合柔性锂离子电池阳极。FESEM显示,纳米硅均匀地嵌入在MWCNTs构建的三维导电网络中,纳米硅和导电载体具有良好的接触,使得界面电阻大幅下降,同时纳米硅在电池充放电过程中具有足够的膨胀空间,保证了材料的结构稳定性和化学稳定性。电化学检测显示,其首次放电比容量达到2024 mAh/g,循环30次后比容量维持在850 mAh/g,展示出良好的循环稳定性和较高的比容量。同时,其制作工艺相比传统涂敷类阳极得以简化,可操作性高,易于实现产业化。     

Transition metal chalcogenide anodes for sodium storage

Owing to the low cost and indefinite availability of sodium resources, rechargeable sodium-ion batteries (SIBs) are now being considered as the most appealing alternatives to their lithium-ion counterparts for large scale applications. On the other hand, transition metal chalcogenides (TMCs) have emerged as potential candidates of SIB anodes due to their versatile material species, ample abundance, low cost, robust nature and high theoretical capacities. However, TMCs still face several challenges like severe volume changes during sodiation/desodiation, inadequate conductivities and large-scale productions. Hence, many traditional and unconventional techniques have been developed to mitigate these issues and obtain high quality electrode materials for practical applications. In this review, recent progress and the rectification stratagems of the problems of TMCs have been summarized firstly. Then, a detailed comparison of transition metal selenides with sulfide TMCs family members was provided to investigate the factors which govern the relative performance improvements of selenides. Besides this, multiple transition metals containing TMCs (M-TMCs) have exhibited intriguingly better performances compared to mono-metal TMCs. Hence, various inspirational features of M-TMCs were discussed. As an outcome of these discussions, we were able to outline several outlooks and prospective solutions for the rectification of potential challenges of TMC anode materials.     

Organic light-emitting diodes having carbon nanotube anodes

Single-walled carbon nanotube (SWNT) films on flexible PET (polyethyleneterephthalate) substrates are used as transparent, flexible anodes for organic light-emitting diodes (OLEDs). For polymer-based OLEDs having the structure: SWNT/PEDOT-PSS:MeOH/TFB (poly(9,9-dioctylfluorene-co-N-(4-butylphenyl)diphenylamine)) + TPD-Si(2) (4,4'-bis[(p-trichlorosilylpropylphenyl)phenylamino]biphenyl) /BT (poly(9,9-dioctylfluorene-co-benzothiadiazole))/CsF/Al, a maximum light output of 3500 cd/m(2) and a current efficiency of 1.6 cd/A have been achieved. The device operational lifetime is comparable to that of devices with Sn-doped In(2)O(3) (ITO)/PET anodes. The advantages of this novel type of anode over conventional ITO are discussed.     

Sulfur-induced porous carbon nanofibers composite SiO as bifunctional anode for high-performance Li-ion storage

Journal of Materials Science - Non-conductivity and volume expansion are the main factors hindering the development of SiO anode materials. To solve these problems, in this work, a bifunctional...     

FeSb@N-doped carbon quantum dots anchored in 3D porous N-doped carbon with pseudocapacitance effect enabling fast and ultrastable potassium storage

Potassium-ion batteries(PIBs)are promising ne15t-generation energy storage candidates due to abundant resources and low cost.Sb-based materials with high theoretical capacity(660 mAh·g^-1)and low working potential are considered as promising anode for PIBs.The remaining challenge is poor stability and slow kinetics.In this work,FeSb@N-doped carbon quantum dots anchored in three-dimensional(3D)porous N-doped carbon(FeSb@C/Nc3DC/N),a Sb-based material with a particular structure,is designed and constructed by a green salt-template method.As an anode for PIBs,it exhibits extraordinarily high-rate and long-cycle stability(a capacity of 245 mAh·g^-1 at 3,080 mAh·g^-1 after 1,000 cycles).The pseudocapacitance contribution(83%)is demonstrated as the origin of high-rate performance of the FeSb@C/NС3DC/N electrode.Furthermore,the potassium storage mechanism in the electrode is systematically investigated through ex-situ characterization techniques including ex-situ transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS).Overall,this study could provide a useful guidance for future design of high-performance electrode materials for PIBs.