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锂离子二次电池负极用碳材料及其储锂机理；粘胶基活性炭纤维对甲苯的吸咐及再生；煤在新型炭材料制备中的应用；碳纤维复合材料商尔夫球杆；碳材料在电双层电容器电极应用的最新研究……     

碳纤维结构表征及其电化学性能研究

碳纤维是一种新型无机纤维材料,具有很高的强度与热稳定性,同时具有双电层电容特性,可应用于高强度耐高温类超级电容器电极基体材料的制备。通过SEM、Raman、XRD、电化学工作站等一系列测试手段对碳纤维进行相关的表征与测试。研究碳纤维结构与电化学性能之间的关系。发现碳纤维具有类石墨结构,使其同时具有良好的双电层电容特性和倍率性能。     

改性膨胀性石墨对硬质聚氨酯泡沫性能和胞体结构的影响

以改性膨胀性石墨和膨胀性石墨为添加剂制备复合聚氨酯泡沫材料,并表征了微观结构、表观密度、压缩性能、保温性能等。改性膨胀性石墨和膨胀性石墨物对材料的微观结构有很大的影响。加入改性膨胀性石墨可以有效提高材料的压缩模量,其压缩模量为143.58MPa,而膨胀性石墨的添加会降低材料的压缩模量,其压缩模量为106.62MPa,而没有添加膨胀性石墨的样品的压缩模量为为108.53MPa。改性膨胀性石墨和膨胀性石墨都可以提高材料的阻燃性能。     

碳纤维石墨化技术研究进展

碳纤维石墨化可以使其结构趋向于理想石墨结构，拉伸模量大幅提升，因此石墨化碳纤维广泛应用在航空航天等尖端技术领域。本文对比分析了碳纤维石墨化设备优缺点，详细介绍了激光超高温加热等新式石墨化方法及促进石墨化进程的相关工艺，进一步从微观结构层面分析影响力学性能的因素，为高模量碳纤维制备技术的研究提供理论及实践参考。指出目前主流的石墨体间接加热技术由于温度限制阻滞了碳纤维模量的进一步提升，克服高温限制且高效高质量、节能环保的石墨化技术是未来的发展趋势；应从组成碳纤维的分子层面去分析把握碳纤维的结构演变，进而优化控制石墨化工艺及设计相关石墨化设备，不断改善碳纤维石墨化结构，逐步趋向于力学性能的理论值。     

聚丙烯腈基高强高模石墨纤维结构研究

以聚丙烯腈纤维为先驱体,经连续热稳定化、碳化处理,制备出T800级碳纤维;进一步经连续石墨化处理后,制备出M50J级石墨纤维。采用SEM、元素分析、XRD和Raman等手段表征了碳纤维截面形貌、化学组成、石墨微晶及取向等结构。与进口M50J石墨纤维相比,国产M50J级碳纤维模量与其相当,但有更高的拉伸强度;同时两者间碳含量和石墨微晶尺寸相当,但国产纤维具有更高的取向程度和石墨化程度。M50J级碳纤维比T800级碳纤维具有更高的碳含量、更完善的石墨微晶结构及取向程度。     

车用启动超级电容器

本发明为一种车用启动超级电容器,超级电容器芯子由包裹隔膜的烧结式氧化镍正极片,连续化活性碳纤维布负极和集流支撑的薄镍片构成。电容芯子通过制作、焊接电流端子后,置于塑料壳体内,注入电解液,封口便得超级电容器成品。该超级电容器具有较高的功率密度和能量密度,且质量轻,成本低,寿命长,适合做各种类型车辆的启动能源,推广应用具有很好价值。     

酚醛基活性碳纤维

酚醛树脂属于难石墨化碳，适宜制造活性碳纤维(ACF)，其特点是碳化活化收率高，制品强度高，比表面积大，孔径分布属于单峰形，吸附容量大；细孔入口形状属于狭缝形，吸脱速度快；制品柔软，深加工性好，它除用于治理环境污染外，还可用于制作防化防毒服和制造超级电容器等。     

PAN基高模量碳纤维成型过程中的结构性能关联性

以实验室自制T800级聚丙烯腈（PAN）基高强中模碳纤维为原料，经连续石墨化处理得到M50J级、M55J级高模量碳纤维，以X射线衍射（XRD）、Raman光谱为表征手段研究了高强碳纤维向高模量碳纤维转变过程中石墨微晶、取向、微孔含量、石墨化度等石墨特征结构的演变规律，并开展了PAN基碳纤维石墨特征结构与力学性能的关联性研究。研究结果表明：在高强碳纤维向高模量碳纤维转变过程中，随着石墨微晶层间距d ₀₀₂的下降以及石墨微晶堆砌厚度L _c的增加，碳纤维的拉伸模量逐渐提升；石墨微晶层间距和微晶取向是影响碳纤维拉伸强度的两个主要因素，石墨微晶层间距d ₀₀₂值增加、石墨微晶取向越高，纤维拉伸强度也越高；在高模量碳纤维的成型过程中，纤维内部微孔含量随着石墨化程度的提高而降低；经过高温石墨化处理后，碳纤维的拉伸强度会随着Raman光谱中无序结构D峰和石墨特征结构G峰积分强度比值I _D /I _G的下降而下降。     

碳纤维石墨化设备的研究与进展

碳纤维石墨化的关键是石墨化设备和高温热处理技术。着重介绍了碳纤维石墨化设备的研究与进展,并对其发展进行了展望,主要内容包括电阻炉、感应炉、太阳炉和等离子体技术。综述了各种石墨化设备的特点和应用,指出改进和更新石墨化设备、大幅度降低生产成本、进一步提高产品性能、实现石墨纤维柔性制造将成为今后研究的重点。     

导电剂种类对双电层电容器工作性能影响的研究

本文采用活性炭YP17为主要电极材料,分别采用微粉石墨、美国卡博特公司生产的导电炭黑Vxc-72和纳米碳纤维VGCF为导电剂,封装成有机体系的超级电容器,通过性能对比,讨论并找出了对提高超级电容器电化学特性效果最佳的导电剂种类。     

Functional polymer–polymer/carbon nanotube bi-component fibers

Bi-component fibers typically combine multiple functions that arise from at least two distinct components. As a result, these fibers can incorporate carbon nanotubes, which impart specific and controllable mechanical, electrical, and thermal transport properties to the fibers. Using gel spinning, sheath-core polyacrylonitrile–polyacrylonitrile/carbon nanotube bi-component fibers with a diameter of less than 20 μm and carbon nanotube concentrations of up to 10 wt% were produced. In these fibers, the carbon nanotubes were well dispersed and aligned along the fiber axis. The fibers exhibited a tensile strength as high as 700 MPa, and a tensile modulus as high as 20 GPa, as well as enhanced electrical and thermal conductivities when compared to the fibers without carbon nanotubes.     

KOH-浸渍-还原法在炭纤维表面制备不同金属纳米催化剂涂层及其应用

为了催化炭纤维原位生长纳米炭纤维／纳米碳管，研究纳米炭纤维／纳米碳管在炭／炭复合材料中的应用，采用KOH-浸渍-还原法在炭纤维上制备纳米催化剂颗粒。首先用KOH处理炭纤维改变其形貌，然后将炭纤维分别在硝酸钴和硝酸镍催化剂前驱体溶液中浸渍，干燥，再用H2气还原制得催化剂颗粒，最后催化热解CO在炭纤维上原位生长纳米炭纤维／纳米碳管。结果表明：KOH处理能使炭纤维表面变得凹凸不平，有效的阻止了催化剂前驱体液体的流动，使涂层均匀；浸渍-还原法能获得粒径小、均匀、适合纳米炭纤维生长的金属颗粒；与Co纳米颗粒相比，Ni分散效果和催化效果更好。     

Comparison of the characteristics of electric double-layer capacitors with an activated carbon powder and an activated carbon fiber

The characteristics of electric double-layer capacitors (EDLCs) with activated carbon powder (ACP), pulverized activated carbon fiber (ACF), and ACF-cloth have been compared. The BET surface areas of the ACP and ACF were estimated to be 1740 and 1970 m² g⁻¹, respectively. In the pore-size distribution curve of the ACP and ACF, the most dominant pore diameter was 1.8 and 1.1 nm for the ACP and ACF, respectively. Disc- and cloth-type of electrodes were fabricated using ACP and ACF. The electrical resistance of the ACF-disc and ACF-cloth electrodes was four orders of magnitudes lower than that of the ACP-disc electrodes. In accordance with the lower electrical resistance of the ACF-disc and ACF-cloth, the d.c. resistance of the EDLC with the ACF-disc and with ACF-cloth was lower than that of the EDLC with the ACP-disc. The highest specific volume capacitance of 28.3 F cm⁻³ (capacitance / volume of total ACF in the EDLC) was achieved with the ACF-disc. In the cyclic voltammograms of the ACF-disc, the stable electric double-layer charging and discharging behavior was observed.     

The performance of electric double layer capacitors using particulate porous carbons derived from PAN fiber and phenol-formaldehyde resin

Activated carbon fibers are known to contain pores with a small resistance for electrolyte migration while possessing a large electrical resistance between the fibers. A carbon powder derived from pulverization of PAN-based carbon fibers was examined as an electrode for electric double layer capacitors using H₂SO₄ as the electrolyte solution. The performance of conventional-type activated carbon powders derived from phenol-formaldehyde resin char was also measured for comparison. The fiber-derived carbon exhibited an electrical resistance comparable to that of the conventional carbons while showed a larger specific capacitance as well as a lesser extent of capacitance decrease at high currents due to a smaller pore resistance. An ultimate capacitance as high as 290 F g⁻¹ can be reached for this fiber-derived carbon powder (with a BET surface area of ≈1300 m² g⁻¹). This large capacitance value was suggested to be associated with the high activity feature of the pore wall.     

Use of carbon nanotubes for strain and damage sensing of epoxy-based composites

The interest in structural health monitoring of carbon fiber-reinforced polymers using electrical methods to detect damage in structures is growing because once the material is fabricated the evaluation of strain and damage is simple and feasible. In order to obtain the conductivity, the polymer matrix must be conductive and the use of nanoreinforcement seems to be the most feasible method. In this work, the behavior of nanoreinforced polymer with carbon nanotubes (CNTs) and composites with glass and carbon fibers with nanoreinforced matrices was investigated. These composites were evaluated in tensile tests by simultaneously measuring stress, strain and resistivity. During elastic deformation, a linear increase in resistance was observed and during fracture of the composite fibers, stronger and discontinuous changes in the resistivity were observed. Among other factors, the percentage of nanotubes incorporated in the matrix turned out to be an important factor in the sensitivity of the method.     

双电层电容器电极材料最新研究进展

对双电层电容器炭基电极材料中已经产业化的和颇具产业化前景的活性炭、碳纳米管、炭凝胶等几种材料进行了综述，分析了它们的性质、特点和研究进展。     

Preparation of High-Performance Internal Tandem Electric Double-Layer Capacitors (IT-EDLCs) from Melt-Spun Lignin Fibers

Activated carbon fibers (ACFs) with large surface area were easily prepared from melt-spun fibers of polyethylene glycol lignin (PEGL). To fabricate electric double-layer capacitors (EDLCs) with a wide potential window and a high energy density in an EDLC package, electrodes (mainly composed of ACFs) were internally laminated and connected in series, in parallel, or in a series/parallel combination. Such resultant EDLCs are termed internal tandem (IT) EDLCs. As expected, the potential window was expanded by the series connection, and the capacitance was increased by the parallel connection. As a result, the energy density in the parallel-connected EDLC was remarkably increased by 66% (16.6 Wh kg^?1) compared with that of a single-cell EDLC. The EDLC with the combination connection showed both advantages. Thus, based on the package weight, the electrochemical performance of the EDLCs was remarkably improved by the IT-type lamination of electrodes.     

活性炭纤维制备双电层电容器

研究了不同材料、比表面积和电解液对比电容的影响，不同比表面积，电解液对循环充电稳定性的影响。结果表明，作为制备双电层电容器的电极材料，活性炭纤维明显好于活性炭，同样基质的活性炭纤维，比表面积大的，比电容不一定大。     

Processing and characterization of epoxy nanocomposites reinforced by cup-stacked carbon nanotubes

The effect of the dispersion, ozone treatment and concentration of cup-stacked carbon nanotubes on mechanical, electrical and thermal properties of the epoxy/CSCNT nanocomposites were investigated. Ozone treatment of carbon fibers was found to increase the surface oxygen concentration, thereby causing the contact angle between water, epoxy resin and carbon fiber to be decreased. Thus, the tensile strength, modulus and the coefficient friction of carbon fiber reinforced epoxy resin were improved. Moreover, the dispersion of fibers in polymer was increased and the electrical resistivity was decreased with the addition of filler content. The dynamic mechanical behavior of the nanocomposite sheets was studied. The storage modulus of the polymer was increased by the incorporation of CSCNTs. But the glass transition temperature decreased with increasing fiber loading for the ozone treated fiber composites. The ozone treatment did affect the morphology, mechanical and physical properties of the CSCNT.     

Electrochemical characterization of carbon nanotubes as electrode in electrochemical double-layer capacitors

Carbon nanotubes uniformly 50 nm in diameter were directly grown on graphite foil. Cyclic voltammetry (CV) shows that the carbon nanotube/graphite foil electrode has a high specific capacitance (115.7 F/g at a scan rate of 100 mV/s) and exhibits typical double-layer behavior. A rectangular-shaped CV curve persists even at a scan rate of 100 mV/s in 1.0 M H₂SO₄ aqueous solution, which suggests that the carbon nanotube electrode could be an excellent candidate as the electrode in electrochemical double-layer capacitors. In addition, the influence of the potential scan rate, aging, and the electrolyte solution on the specific capacitance of nanotube electrodes was also studied.