制备多孔锂离子电池电极的研究进展

着重介绍近年来多孔锂离子电池电极材料合成的研究进展。软模板剂法合成温度较低,生成的多孔材料孔型可控性好。纳米铸造、凝胶结晶及生物材料作底物等硬模板剂方法可在温度较高的条件下合成电极材料,该材料多为介孔和大孔材料。电极沉积法、超声波降解法、水热合成法等非模板剂法合成条件较为简单,合成材料孔径分布较广。     

氮杂化介孔碳制备方法及在超级电容器中的应用进展

氮杂化介孔碳是在有序介孔碳的骨架中掺入氮原子部分取代碳原子形成的多孔物质,是一种具有优异性价比的新型碳材料。综述了氮杂化介孔碳的各种制备方法及其特点,重点介绍了混合聚合物炭化法和共聚物炭化活化结合法等新型的氮杂化介孔碳的制备方法;介绍了制备氮杂化介孔碳的碳、氮原料的来源和特点;总结并提出了提高氮杂化介孔碳比电容的途径和方法;提出了导电性氮杂化介孔碳的制备新方法。建议将氮杂化介孔碳的制备和酚类废物处理结合起来,以实现酚类废物的综合利用;建议将掺氟氧化锡原位引入氮杂化介孔碳的制备中,催化活化得到导电性氮杂化介孔碳材料。     

锂硫电池硫基碳正极材料的研究进展

用于锂硫电池的碳质材料具有优异的力学、电学、导热性能,可调的孔结构以及丰富的表面特性,能有效地限制多硫化物的溶解,改善锂硫电池的电化学性能。因此,本文分别从一维碳、二维碳和三维碳这3个方面综述了锂硫电池硫基碳复合正极材料的研究进展,探讨了改性硫基碳正极材料的制备方法和结构设计。分析表明,高比表面积和高孔容积的多孔纳米碳材料对提高锂硫电池电化学性能而言至关重要,并提出用金属硫化物掺杂的有序介孔碳复合材料作为锂硫电池的正极材料能促进锂离子在正负极间的迁移,提高锂硫电池的循环稳定性和活性物质利用率。     

生物-共沉淀法合成高性能磷酸铁锂介孔复合材料

本文利用生物-共沉淀新方法合成磷酸铁锂材料.以微生物为模板与金属离子和磷酸根通过矿化反应和共沉淀反应,形成沉淀物.经热处理后得到具有介孔结构的LiFePO4/C复合材料,其介孔尺寸在3～25nm之间;合成材料在0.1C时其初次放电比容量达到150mAh/g;高倍率下具有良好的循环性能,经过100次充放电循环后,其比容量保持率高达95％;充放电平台稳定,其电压稳定在3.4V左右;循环伏安测试结果显示,电池反应在3.4V左右极化现象不明显.合成材料其电化学性能的提高主要是由于其介孔结构和原位复合碳的存在,从而可显著提高锂离子的传导率和电子的电导率.本方法对制备高性能锂离子电池正极材料具有重要的应用价值.     

CNT@SnO_2@C纳米复合物的制备及其储锂性能

为改善锂离子电池负极循环性能,提高其安全性和稳定性,制备了氧化锡-碳锂离子电池负极材料。以有机聚合物碳纳米管(PNT)为前驱物骨架、沸石咪唑骨架材料-8(ZIF-8)为碳基修饰材料、纳米片状氧化锡为主体材料,合成出一种CNT@SnO_2@C纳米复合物,该材料的比表面积为125. 6 m~2/g。在作为锂离子电池负极材料应用时,2 A/g电流密度下循环600次,容量依然可以保持在878 mAh/g,具备优异的高比容量和持久的循环性能。     

蛋黄壳型介孔纳米球的研究进展及应用

蛋黄壳型介孔纳米球结合了实心和中空核壳结构介孔纳米球的特点，化学性质稳定，具有均匀的形态、良好的分散性、开放有序的介孔通道和大小可调的空腔，吸引了越来越多研究者的关注。主要介绍了蛋黄壳型介孔纳米球的制备方法，常见的方法有选择刻蚀、模板组装、瓶中造船、奥斯特瓦尔德成熟化、基于柯肯德尔效应和电偶置换，阐述了其在催化、生物医学、吸附、锂离子电池和太阳能电池等方面的应用，并对蛋黄壳型介孔纳米球研究的发展趋势进行了展望。     

介孔碳微球的合成及其应用研究进展

目前,介孔碳微球的合成主要有硬模板和软模板两种方法。硬模板是将碳前驱体通过溶剂挥发填充到已合成的球形介孔材料(硬模板)中,然后热处理掉硬模板得到介孔碳微球;软模板则是以三嵌段共聚物F127做为模板剂,酚醛树脂作为碳源在水热条件下制备出介孔碳微球。介孔碳微球在超级电容、锂离子电池、气体储存、生物医药等领域获得广泛应用,然而在摩擦润滑领域的研究却未见报道。结合本课题组的前期研究提出了其在摩擦领域的研究思路并展望了其应用前景。     

凝胶聚合物电解质的电化学性能

用化学交联法制备了凝胶聚合物电解质.聚烯烃多孔膜支撑的凝胶聚合物电解质具有优良的电化学性能, 室温电导率为1.01×10^-3S•cm^-1,锂离子迁移数为0.41,在Al电极上的氧化起始电位达到4.2 V以上.采用聚烯烃多孔膜支撑的凝胶聚合物电解质制备了聚合物锂离子电池,并研究了工艺条件对聚合物锂离子电池电化学性能的影响.研究的工艺条件包括：单体添加量和电极组合方式.优化后的聚合物锂离子电池具有良好的电化学性能,1 C放电容量为0.2 C放电容量的93.2%,经100次1 C循环后的剩余容量仍在80%以上.     

锂离子电池隔膜研究进展

锂离子电池隔膜是锂离子电池的重要组成部分,介绍了锂离子电池隔膜材料及其改性方法,综述了隔膜的制备与性能包括孔结构、孔隙率、热稳定性、透气率和电化学性能等方面的研究进展,对提高锂离子电池隔膜热稳定性、机械性能以及与电解液的亲和性并降低其生产成本的研究仍倍受关注。     

文摘

正电纺丝制备掺氮多孔炭纳米纤维布用作锂离子电池负极材料[刊,中]/楠顶,黄正宏,康飞宇,等//新型炭材料,2016,31(4):393-398选取聚丙烯腈和三聚氰胺为碳前驱体和氮前驱体,通过电纺丝和后续的炭化和水蒸气活化过程,制备了一种具有自支撑结构,无需任何导电剂和粘结剂,直接用作电极的用于锂离子电池负极的掺氮多孔炭纳米纤维布。结果表明,此多孔炭纳米纤维布具有无纺交联的纳米纤维形态、独特的微孔结     

Porous SnO2 nanospheres as sensitive gas sensors for volatile organic compounds detection

Porous SnO(2) nanospheres with high surface areas have been synthesized through a solvothermal method in the absence of any templates. The structure and morphology of the resultant products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption-desorption technique. The as-prepared SnO(2) porous nanospheres with the diameters ranging from 90-150 nm are composed of small nanocrystals with average sizes of less than 10 nm. Results demonstrated that the formation of porous SnO(2) nanospheres is ascribed to etching the center part of the nanospheres. It was found that hydrochloric acid and NaClO played important roles in determining the final morphologies of the porous SnO(2) nanospheres. The gas sensing properties of the as-prepared porous SnO(2) nanospheres were investigated. By the comparative gas sensing tests, the porous SnO(2) nanospheres exhibited a superior gas sensing performance toward ppb level 2-chloroethanol and formaldehyde vapor, implying promising applications in detecting toxic volatile organic compounds (VOCs).     

Small quantities of cobalt deposited on tin oxide as anode material to improve performance of lithium-ion batteries

In this report, we present a hybrid structure involving a small quantity of Co element uniformly deposited on porous SnO(2) spheres as stable and high capacity anode materials for lithium-ion batteries. Specifically, Co element deposited on SnO(2) nanomaterials exhibited an exceptional reversible capacity of 810 mA h g(-1) after 50 cycles which is higher than the pure SnO(2) electrode. Based on the experiments results, a possible mechanism for the change of this structure during lithium ion insertion/extraction was proposed. The minute quantity of Co element uniformly deposited on SnO(2) spherical structure could prevent Sn aggregation during charging-discharging, and high porosity of the spherical structure allowed the volume expansion during lithium ion alloying/dealloying. The SnO(2) deposited with small quantities of Co element as electrode facilitated improved performance of lithium ion batteries with higher energy densities.     

Constructing porous ZnO/SnO2 nanocomposites for the detection of methane at low operating temperature

Journal of Porous Materials - Aimed at detecting methane (CH4) gas at low operating temperature, porous ZnO/SnO2 nanocomposites were constructed through a simple two-step method. Pure SnO2 with a...     

Synthesis and Characterization of SnO2 on Porous Silicon for Photoconversion

Silicon - A photoconversion device was fabricated based on SnO2 film prepared by a chemical spray pyrolysis technique. The SnO2 nanofilms were grown on the porous silicon (PS) nanosurface. Various...     

SnO2基导电陶瓷靶材的制备及应用性能表征

为了获得高质量的SnO2薄膜,我们需要制备高密度、高导电的优质SnO2靶材。这里以分析纯的SnO2、Sb2O5粉体为制备原料,采用冷等静压加上常压烧结方法制备高导电性Sb∶SnO2(ATO)陶瓷靶材。用X射线衍射(XRD)和扫描电子显微镜(SEM)分析靶材的化学成分和微观形貌并系统研究了不同的成型压力对靶材电学特性和致密度的影响。结果表明:成型压力的大小对于ATO靶材本身的致密度及电学特性都有很大的影响。成型压力为15MPa时,ATO靶材的电阻率最小,为0.38Ω.cm;SnO2靶材的收缩率达10.71%,靶材的致密度为95%;靶材可在射频磁控溅射仪下正常工作,并成功在玻璃基片上沉积性能良好的高红外反射透明导电SnO2薄膜。此制备过程操作方便,工艺简单,降低了靶材的成本,从而能够大大扩大透明导电薄膜的应用领域。     

SnO2/ZnO复合中空纤维材料的制备及其光催化性能

采用天然棉花为模板制备了具有高光催化活性的SnO2/ZnO复合中空纤维光催化材料;利用X-射线衍射(XRD)、扫描电子显微镜(SEM)技术对其相结构和形貌进行了表征;以亚甲基蓝(MB)的脱色降解为模型反应,考察了Sn4+和Zn2+物质的量比为0.1∶1时煅烧温度对其催化性能的影响。实验结果表明:制备的样品为复制了棉花纤维模板形貌、具有中空结构的SnO2和ZnO半导体复合材料(SnO2/ZnO);煅烧温度对材料SnO2/ZnO的结晶度、晶粒大小﹑表面微结构和催化性能等有显著影响;650℃左右所得样品在太阳光下的催化活性最好,1 h可使MB溶液的脱色降解率达100%;该材料易于离心分离,具有良好的催化活性和重复使用性能。     

Ti/SnO2+Sb2O3/PbO2电极在硫酸溶液中Cr3+氧化的电化学性能

对用聚合前驱体溶液通过热分解法制备的Ti/SnO2+Sb2O3/PbO2电极在硫酸溶液中Cr3+电化学氧化的电化学性能进行了研究. 分别测定了以Ti/SnO2+Sb2O3/PbO2和PbO2为阳极，硫酸介质中Cr3+电化学氧化过程的极化曲线、抗腐蚀性以及不同操作电流密度、Cr3+浓度、反应温度、硫酸浓度下的电流效率. 实验结果表明，聚合前驱体溶液通过热分解法制备的Ti/SnO2+Sb2O3/PbO2电极与PbO2电极相比具有更高的电催化活性和抗腐蚀性.     

Synthesis of polymer/inorganic nanocomposite films using highly porous inorganic scaffolds

Polymeric/inorganic nanocomposite films have been fabricated through a combination of flame-spray-pyrolysis (FSP) made inorganic scaffold and surface initiated polymerization of cyanoacrylate. The highly porous structure of pristine SnO(2) films allows the uptake of cyanoacrylate and the polymerization is surface initiated by the water adsorbed onto the SnO(2) surface. Scanning electron microscopy study reveals a nonlinear increase in the composite particle size and the film thickness with polymerization time. The structural change is rather homogeneous throughout the whole layer. The composite is formed mainly by an increase of the particle size and not by just filling the existing pores. High-resolution transmission electron microscopy imaging shows SnO(2) nanoparticles embedded in the polymeric matrix, constituting the nanocomposite material. Thermogravimetric analysis indicates that the porosity of the nanocomposite films decreases from 98% to 75%, resulting in a significant enhancement of the hardness of the films. DC conductivity measurements conducted in situ on the nanocomposite layer suggest a gradual increase in the layer resistance, pointing to a loss of connectivity between the SnO(2) primary particles as the polymerization proceeds.     

SnO₂ nanosheet hollow spheres with improved lithium storage capabilities

In this work, we employ new chemistry to grow tin oxide nanosheets in the gel matrix of sulfonated polystyrene hollow spheres. After calcination in air, hierarchical hollow spheres assembled from SnO(2) nanosheets can be obtained. In virtue of the porous shell structure and internal voids, these SnO(2) hierarchical nanosheet hollow spheres exhibit improved lithium storage capability.     

Service life of Ti/SnO2–Sb2O5 anodes

The service life of SnO2–Sb2O5 coated anodes prepared by the spray pyrolysis technique using Ti or Ti/IrO2 substrate, was studied under galvanostatic conditions (100mAcm–2 in 1m H2SO4 at 25°C. The results showed that the presence of an IrO2 interlayer between the Ti substrate and the SnO2–Sb2O5 coating (Ti/IrO2/SnO2–Sb2O5 anode) strongly increases the service life of the anode. This beneficial action of the IrO2 interlayer was attributed to its high anodic stability and its isomorphous structure with TiO2 and SnO2. Cyclic voltammetry and steady-state polarization curves showed that the electrochemical behaviour of the Ti/IrO2/SnO2–Sb2O5 electrode lies between the behaviour of the Ti/IrO2 and the Ti/SnO2–Sb2O5 electrodes due to incorporation of IrO2 in the SnO2–Sb2O5 coating during its preparation.