PAN-Mg(OH)_2多孔复合碳材料的制备及其在染料吸附和超级电容器中的应用

采用Mg(OH)_2预填充PAN基膜为前驱体制备了具有多级孔结构的复合碳材料,制备的复合碳材料含有54. 1%C、26. 8%O、6. 2%N和6. 5%Mg,可将其用作超级电容器的电极材料和染料吸附剂使用。作为超级电容器时,比电容在1 A/g扫描速率下可达236 F/g,在10 A/g扫描速率下可达206 F/g左右,比电容保持率高达87%。优良的倍率性能与多孔结构的层次性有关。该复合材料作为染料吸附剂使用时,对甲基橙(MO)有很高的吸附能力,当染料质量分数为800μg/g时,其饱和吸附量可达1 170 mg/g。     

间苯二酚—甲醛基碳气凝胶的制备及其应用

超级电容器是新型储能器件之一，电极材料是影响其性能的关键因素。以间苯二酚和甲醛为主要原料，采用反相悬浮聚合的方法，通过常压干燥和碳活化过程获得高比表面积的碳气凝胶材料。制备的碳气凝胶材料比表面积达到1 783.6 m2/g，具有丰富的微孔结构，其比电容达到122.4 F/g，作为3 000 F超级电容器的电极材料，经过循环充放电测试，证实其具有良好的循环稳定性。以常压干燥方式制备的碳气凝胶应用于超级电容器中，表现出的电化学性能优异，不仅提供了碳气凝胶产业化新思路，也表明碳气凝胶在储能领域具有非常广阔的应用前景。     

梧桐絮制备多孔纤维碳材料及其在超级电容器中的应用

以法国梧桐絮为原料、KOH为活化剂,通过碳化制备多孔纤维碳材料,并在此基础上组装了超级电容器器件。通过SEM、EDS、XRD、Raman、FTIR、BET等对制备的多孔纤维碳材料进行表征,并研究了多孔纤维碳材料电极的电化学性能。结果表明:在扫描速率为50 mV·s~(-1)时,800℃下碳化制备的梧桐絮多孔纤维碳材料电极的比电容可以达到236 F·g~(-1);所组装电极在循环10 000次后,比电容仍维持原来的99.8%,表明梧桐絮多孔纤维碳材料在超级电容器领域有巨大的应用潜力。     

介孔碳/石墨烯复合材料的制备及在超级电容器中的应用

以棕榈树须作为天然碳源和模板,利用化学气相沉积法制备出介孔碳/石墨烯复合材料,研究了复合材料的超级电容器性能。通过扫描电子显微镜、Raman光谱、比表面及孔径分析等对材料的形貌、结构、比表面积和孔径分布进行表征。采用循环伏安和恒电流充放电方法研究了超级电容器在1 mol/L H_2SO_4电解质溶液中的电化学性能。在三电极体系和1 A/g条件下,材料电容达到144 F/g。在二电极体系下,材料电容达到138 F/g,比三电极略有降低。同时,倍率性能优异,20 A/g条件下电容为78 F/g,与三电极体系接近。     

氮掺杂石墨烯/碳纳米管/无定形炭复合材料制备及其电化学性能

碳基复合材料被认为是超级电容器广泛应用最有前景的电极材料之一。本文使用氧化石墨烯（GO）、硝酸钴［Co(NO₃)₂］、三聚氰胺为原料,利用钴对高温下热解碳源的催化作用,制备得到了氮掺杂石墨烯/碳纳米管/无定形炭（NC）复合材料,并测试了其电化学性能。探究了金属和三聚氰胺添加量对碳基复合材料结构和性能的影响,研究发现,在添加量分别为0.02mmol和0.3g时,制得的样品具有大比表面积（380.5m²/g）和高掺氮质量分数（6.29%）,并在三电极系统中体现出优异的电化学性能,电流密度为0.5A/g时样品的比电容为137.1F/g,5A/g时比电容为113.5F/g,保持率为88.5%,具有优异的倍率性能,在循环5000圈后样品的容量保持率为104%,具有良好的循环稳定性,这归因于三维结构可以加快充放电过程中的离子转移和氮掺杂可提高材料润湿性和贡献部分赝电容,为超级电容器电极材料的制备提供了理论借鉴。     

纳米二氧化锰超级电容器电极材料的制备及改性

采用溶胶-凝胶法制备了二氧化锰超级电容器电极材料.借助X射线衍射和扫描电镜等测试手段对其进行了物理结构表征.结果表明,产品为颗粒状的纳米α-二氧化锰,电极比容量为146 F/g.通过在煅烧过程中掺入不同质量比的氧化铝来考察氧化铝添加量对二氧化锰电极材料电容特性以及电容量的影响.实验结果表明,添加氧化铝后的二氧化锰电极材料比未添加的有较好的循环伏安特性,且当添加质量分数为1%时,电极比容量达到最大,为165 F/g,经过200次循环后容量仍保持在90%以上.     

碳化物衍生碳的制备及其应用研究进展

碳化物衍生碳（CDC）由碳化物作为一个特立独行的物体组成，它从间隔中提取金属元素，从而产生一种新的碳物质。综述了CDC的常见命名及结构、衍生碳的特点，介绍了CDC的制备方法，论述了其在摩擦涂层、气体吸附、催化剂载体和电极材料等领域具有的科学研究和应用潜力。最后总结了CDC的结构与组成在实际应用中的优势，展望了其在将来完成商业化的可能性。     

螺旋碳管插层还原氧化石墨烯制备自组装超级电容器

石墨烯基超级电容器电极面临着层间堆叠的问题，使用独特的螺旋碳管（HCNTs）插层还原氧化石墨烯（rGO），采用自组装的方法构建3D全碳网络，直接用于无黏结剂的超级电容器电极（rGO&HCNTs），可有效减少石墨烯的堆叠。rGO包裹具有类弹簧结构的HCNTs，这种3D网络极大地增加了电极的比表面积，提高了电荷转移速率，并且全碳结构具有较好的稳定性。rGO&HCNTs电极在0.25 A/g的电流密度下，表现出296 F/g的比电容，在1 A/g的电流密度充电/放电循环3 000圈之后，比容量为初始的89%。这种复合材料是高性能超级电容器及柔性电极的潜在候选材料。     

微波法制备煤基超级电容器用活性炭

以微波为热源，优质无烟煤为原料，KOH为活化荆制备超级电容器用高比表面积活性炭电极材料。研究结果表明：KOH与无烟煤按3：1的质量比混合，微波辐射7分钟时，制备的活性炭单电极比电容量达301F／g。讨论了微波辐射时问，活化剂与无烟煤质量比对活性炭比电容的影响。考察了以该活性炭为电极材料的超级电容器的充放电性能。     

吸附电活性染料的活性炭电极电化学性能

采用商用活性炭（AC）吸附二元混合染料亚甲基蓝（MB）和胭脂红（AR18）,制备得到AC/(MB+AR18)电极材料。比较单一活性炭（AC）和吸附不同浓度的二元混合染料后的活性炭[AC/(MB+AR18)]的电化学性能。三电极体系的测试结果表明：在1mol/L H₂SO₄电解液中,当电流密度为1A/g时,吸附了浓度为400mg/L污染物的AC/(MB+AR18)比电容为182F/g,高于单一AC的比电容（109F/g）。随后选用性能最优的AC/(MB+AR18)-400作为电极材料,组装对称超级电容器器件,发现工作电压窗口从只用AC组装的对称超级电容器的1.1V提高到1.5V,电流密度为0.75A/g时,功率密度为843.84W/kg,能量密度可达32.23W·h/kg,远远高于AC组装的超级电容器(4.74W·h/kg),说明MB和AR18不仅为AC提供额外的法拉第电容,同时有助于提高其工作电压窗口。     

In-situ thermal activation of carbide-derived carbon

Microporous carbons attract high interest due to their application as a medium for gas storage, catalyst support or electrode material in lithium ion batteries or supercapacitors. Carbide-derived carbons (CDC) produced by halogenation of carbides exhibit a narrow pore size distribution and a tunable pore and microstructure by choosing the appropriate carbide precursor and chlorination temperature. However, the pore volume is limited by the amount of metal in the carbide structure, and the variation of pore size by varying the process conditions is not possible for all carbides. With an in-situ thermal activation in CO₂ parallel to the chlorination, the porosity of the CDC materials can be further increased. This improved carbide-derived carbon process also allows producing novel pore structures which vary in the meso- to micropore ratio from the outside to the center of the particle. Thereby also the boarder case of shell-like carbon structures showing different pore size distributions in the shells can be produced. For this in-situ activation and chlorination of carbides the influence of the processing, the concentration of CO₂ and activation time on the pore structure of CDC was studied.     

Synthesis, characterization and energy-related applications of carbide-derived carbons obtained by the chlorination of boron carbide

A nanoporous carbide-derived carbon (CDC) was synthesized by chlorination of boron carbide powder using hydrogen chloride as the reactive gas. The structure and texture of the CDCs were characterized by X-ray diffraction, high-resolution transmission electron microcopy and nitrogen adsorption at 77 K, which confirmed a structural and textural dependence on chlorination temperature and reaction time. The CDC technique to produce porous carbons is very attractive because it can obtain carbons with desired structure and porosity and the CDCs produced here show great potential for energy-related applications. Used as hydrogen storage materials, the hydrogen uptake capacity could reach 1.06 wt.% at 77K and 1 bar. When tested as electrodes for supercapacitors, specific surface capacitance value up to 0.403 F m⁻² and a capacitance retention ratio up to 86% (at a voltage scan rate of 50 mV s⁻¹) could be obtained.     

Fast production of monolithic carbide-derived carbons with secondary porosity produced by chlorination of carbides containing a free metal phase

Hierarchical structured carbide-derived carbons (CDC) are produced by high temperature chlorination of silicon carbides containing free silicon (Si/SiC). The influence of free silicon in the precursor carbide on the resulting pore and carbon structure and production rate is studied. The two phases – free silicon and silicon carbide – of Si/SiC gives the possibility to synthesize a monolithic carbon with the typical microporous character and narrow pore size distribution combined with larger voids in the micrometer range, while the carbon structure itself stays unchanged. The study revealed that using Si/SiC material increases the production rate for carbide-derived carbons dramatically, due to higher reactive surface area and lower mass transfer limitations, which allows for the time effective production of larger monoliths.     

Electrochemical energy storage in ordered porous carbon materials

Highly ordered porous carbon materials obtained by a replica technique have been used for supercapacitor application and electrochemical hydrogen storage. For the preparation of the well-tailored carbons, MCM-48, SBA-15 and MSU-1 molecular sieves served as templates, whereas a sucrose solution, propylene and pitch were the carbon source. A careful physico-chemical characterization (CO₂ and N₂ adsorption, X-ray diffraction, electron microscopy observations) allowed to estimate the total surface area, the pore size distribution, the micro/mesopore volume as well as the structure and the microtexture of the investigated carbons. The specific capacitance (F/g) and the hydrogen adsorption capacity in the carbon nanopores were correlated with the microtextural properties. Especially, a linear dependence has been found between the capacitance or the amount of electrochemically stored hydrogen and the ultramicropores (pores smaller than 0.7 nm) volume. It clearly indicates that in these carbons: (a) the major part of the electrical double layer is charged with non-solvated ions; (b) ultramicropores play a determinant role for hydrogen storage.     

A cubic ordered, mesoporous carbide-derived carbon for gas and energy storage applications

A hierarchical and highly porous carbide-derived carbon (CDC) was obtained by nanocasting of pre-ceramic precursors into cubic ordered silica (KIT-6) and subsequent chlorination. Resulting CDC replica materials show high methane and n-butane uptake and excellent performance as electrode materials in supercapacitors.     

Mechanism of formation and electrochemical performance of carbide-derived carbons obtained from different carbides

Porous carbide-derived carbons (CDCs) are synthesized from different carbide (VC, TiC, NbC) as electrode materials for electrochemical capacitors. The process of carbide–carbon transformation is investigated by observations at different carbide/CDC interfaces. It is found that the restructuring process has much influence on formation of microstructure as well as the resultant electrochemical performance. The carbon structure in the produced CDC is well in accordance with that formed at the carbide/CDC interface, indicating that the microstructure in the produced CDC is decided by re-bonding of the residual carbon atoms. It is further found that the internal stress during carbide–carbon transformation has much influence on the CDC microstructure. In addition, the microstructure in CDCs is dependent on the volumetric concentration of carbon atoms in carbide precursor. Lower volumetric concentration of carbon atoms facilitates the formation of CDC with short and curved graphene structure, which owns easily accessible pores and large specific surface area, and thus high electrochemical performance for ultracapacitor. A novel strategy that controlling microstructure of CDC through controlling the volumetric concentration of carbon atoms in carbide precursor is presented. This strategy is very effective to form designed microstructure of CDC for electrochemical applications.     

Structural evolution of carbide-derived carbons upon vacuum annealing

Microstructure and surface moieties of porous carbons play a significant role in affecting their performance in a variety of applications. While it is well known that high-temperature treatments of porous carbons can influence the microstructure, no systematic studies have been done on carbide-derived carbons. We show that vacuum annealing increases the pore volume and specific surface area of titanium carbide-derived carbon with no significant change in the pore size up to 1500 °C. This treatment produces porous carbons with subnanometer porosity and a specific surface area up to 2000 m²/g, while treating the samples at temperatures above 1600 °C increases the pore size above 1 nm because of graphitization and collapse of the micropore structure. The results demonstrate that vacuum treatment can be used to further tune the pore structure and potentially the surface functionality of carbide-derived carbons for supercapacitor electrodes, gas chromatography, sorption, sensing and other applications. Vacuum annealing of carbide-derived carbon is therefore a suitable alternative to conventional microstructure modification methods, such as gas or liquid phase activation, which are subject to substantial sample loss and result in additional surface functionalization.     

High surface area carbide-derived carbon fibers produced by electrospinning of polycarbosilane precursors

Highly porous carbide-derived carbon fibers have been synthesized by electrospinning of polycarbosilane with subsequent pyrolysis and chlorination. The resulting ultrathin fibers show specific surface areas up to 3116 m² g⁻¹ and very high storage capacities for hydrogen up to 3.86 wt.% at 17 bar and 77 K. Due to the outstanding adsorption performance and other properties such as high temperature stability and the unique CDC fiber shape, this new kind of fiber material offers promising possibilities for several applications like air or liquid filters or textiles for protective clothing. Application as a flexible electrode material for supercapacitors is conceivable.     

CoO@CuO电极材料制备及超级电容性能研究

超级电容器因具有功率密度高、充放电速率快、循环使用寿命长等优点而备受关注。CoO是一种优良的超级电容电极材料,理论比容量可以达到4 292 F·g^-1,但其电导率较低,而且充放电过程中会产生体积膨胀,导致其实际比容量低于理论比容量。为此,本文首先采用热氧化法在泡沫铜导电集流体上生长CuO纳米线阵列,然后采用化学浴沉积法在CuO纳米线表面沉积CoO层级结构,制备核壳结构CoO@CuO电极材料。该电极材料在电流密度为2 mA·cm^-2时的比容量可达到1.043 0 F·cm^-2(117.145 3 F·g^-1),并表现出了良好的电容保持率。     

一种生物炭基柔性固态超级电容器的制备及性能研究

利用固体农业废弃物玉米秸秆作为原料,经高温煅烧,KOH刻蚀获得具有较大比表面积的多孔生物炭材料,并采用粉末X射线衍射仪(XRD)、场发射扫描电镜(FE-SEM)、红外光谱(FT-IR)、拉曼光谱(Raman)以及比表面积和孔径分析仪(BET)等表征手段,研究其物理、化学结构和微观形貌。结果表明,所制备的生物炭材料具有发达的“微孔-中孔-大孔”三维贯通多级孔道结构,比表面积高达1228 m2·g^-1。将其作为电极材料,与H₂SO₄/PVA凝胶电解质可组装成为具有柔性的全固态超级电容器。利用循环伏安测试(CV)、恒电流充放电(GCD)以及交流阻抗测试(EIS)对柔性超级电容器电化学性能进行了测试。在电流密度为1.0 A·g^-1的条件下,其比容量可达125 F·g^-1。该器件具有良好的机械柔性和电化学稳定性,将其从0°弯曲至180°的过程中,比电容保持率约为93.5%;以不同弯曲角度将其连续弯折100次后,仍能保持较高的比电容。此外,在弯折角度180°、充放电电流密度为5.0 A·g^-1 的条件下经过500次循环充放电后,比电容值保持率约为95.6%,库仑效率约为94.9%。说明所制备的柔性超级电容器具有优异的充放电性能和长效循环稳定性。作为一种柔性、质轻、便携的储能装置,在可穿戴电子器件领域内具有潜在应用价值。同时该方法也为固体农业废弃物玉米秸秆的高附加值转化利用和新型绿色能源器件创新研制提供了新的技术途径。