氢氧化钾活化法制备淀粉活性炭电极材料

以KOH为活化剂、氧化交联淀粉为原料制备了超级电容器用电极材料.最佳工艺条件是:活化温度850℃,活化保温1.5 h,碱炭质量比为2∶1.在该条件下制备的淀粉活性炭具有较高的比表面积(1 493.9 m2/g)和高比容量(218 F/g).通过氮吸附表征其孔结构.以其作为电极材料组装在模拟超级电容器中进行充放电性能和循环伏安法测试,在300 mg/g KOH水系电解质溶液、较高电流密度下,最佳制备工艺条件下所制备的活性炭表现出较好的电容特性.     

MnO2/碳球复合材料的制备及其电化学性能的研究

利用碳球为还原剂,在中性KMnO₄溶液中制备出MnO₂/碳球复合材料,并对其结构和电化学性能进行了研究。结果显示,随着碳球含量的增加,MnO₂/碳球复合材料的循环稳定性提高,但比电容量降低;当碳球质量分数为35%时,MnO₂/碳球复合材料的比电容量在50mA/g的电流密度下达到181F/g。分别采用KOH活化和混酸氧化的碳球为还原剂,可以有效地提高MnO₂/碳球复合材料的比电容量和循环稳定性,相应复合材料的比电容量分别达到192F/g和218F/g,而且经过500次的充放电测试,仍然保持为184F/g和192F/g。     

酚醛树脂基微孔炭的制备及双电层电容特性

以热固性酚醛树脂为原料,采用CO2物理活化法制备双电层电容器,用高比表面积活性炭.由氮气吸附法测定活性炭的比表面积和孔结构,采用循环伏安、交流阻抗和恒电流充放电考察其在3000/KOH水溶液中的电容特性.结果表明,随着活化时间的延长,所得活性炭收率下降,比表面积、总孔孔容和质量比电容则不断增加;具有高比表面积和宽孔径分布的试样APF957质量比电容值最高,电流密度由50 mA/g提高到1000 mA/g时,其放电比电容由211.6 F/g降低到196.5 F/g,容量保持率达到9300/,显示出良好的功率特性.     

中孔炭的制备及其电化学电容性能研究

以正硅酸乙酯为模板硅源,间苯二酚和甲醛为炭源,通过溶胶一凝胶反应,制得中孔炭材料．采用SEM、XRD、N2吸附等温线研究了炭材料的形貌和结构;采用电化学工作站研究了炭材料的电化学电容性能．结果表明,炭材料为石墨化的无序结构,比表面积为1313m2·g-1,孔径约10nm．在6mol·L-1H2s04中表现出良好的电化学电容性能．当放电电流密度为0．05A·g-1时,炭材料的质量比电容为265F·g-1,其容量保持率达92．8％,具有良好的电化学稳定性和可逆性．     

碱炭比对活性炭孔结构及电容特性的影响

以酚醛树脂为原料、KOH为活化剂制备双电层电容器用高比表面积活性炭．考察KOH与酚醛树脂炭的质量比对所制得的活}生炭的吸附性能、孔径分布和比电容的影响．实验结果表明,随着碱炭比的增大,所得活性炭的BET比表面积、总孔容积和中孔容积不断增大,碘吸附值和亚甲基蓝吸附值也不断增大,比电容则先增大后减小并在碱炭比为4时达到最大值74．2F／g．以这种高比表面积活性炭组装成的电容器具有良好的充放电性能和循环性能,既能在大电流下快速充放电也能在小电流下缓慢充放电。     

分级多孔纳米炭纤维的结构及电容性能

以酚醛树脂为碳源、PVP为纺丝助剂、纳米MgO颗粒为模板剂,通过静电纺丝法制得酚醛树脂基纳米炭纤维,经过炭化、KOH活化、酸洗后得到分级多孔纳米炭纤维,利用SEM、XRD、XPS、拉曼光谱仪及氮气吸脱附实验,对所制多孔纳米炭纤维的结构和形貌进行表征,并将其作为模拟电容器的电极,利用循环伏安、恒电流充放电及交流阻抗方法测试了材料的电化学性能。结果表明,KOH活化引入了数量可观的微孔,所得纳米炭纤维表现出明显的"微孔-中孔-大孔"分级孔分布的特点,其比表面积达到1058.4m~2/g,总孔容为1.64cm~3/g。电化学测试结果表明,所制分级多孔纳米炭纤维在6mol/L KOH电解液中显示出优异的电容性能,在0.2A/g的电流密度下,其放电比容量达到198F/g,在20A/g电流密度下,电容保持率达到65%。     

黄铁矿型FeS2纳米微球的制备及其超级电容性能研究

采用简单的溶剂热法,一步合成黄铁矿型FeS2纳米微球,并研究其作为超级电容器电极材料的电化学性能.用X射线衍射(XRD)、扫描电镜(SEM)和氮气吸脱附法表征材料的结构和形貌,通过循环伏安(CV)、恒电流充放电(GCD)和电化学交流阻抗(EIS)测试材料在3种常见电解液(6 M KOH,6 M NaOH和1 M Na2...     

超级电容器用新型微晶炭的结构及其电容性能

以热处理后的煤沥青焦为原料,采用KOH活化法制备了具有较小比表面积(＜200m~2/g)的系列微晶炭.采用N_2吸附、X射线衍射(XRD)和X射线光电子能谱(XPS)等手段表征了微晶炭的孔结构、微晶结构以及表面化学性质,研究了微晶炭作为超级电容器电极材料在1 mol/L的四乙基四氟化硼酸铵盐/碳酸丙烯酯电解液体系中的电容性能.结果表明:制得的微晶炭具有大量类石墨微晶和较高的石墨化度,d_(002)(晶面层间距)为0.356～0.666 nm,表面含碳量大于95%;活化6 h后,在4.0 V下微晶炭的质量比电容高达139 F/g.微晶炭的储电行为包括插层电容和双电层电容两部分,其中电活化所造成的插层电容是决定微晶炭最终比电容的主要因素,插层电容主要由电极材料的石墨化度决定.     

Electrochemical reduction of graphene oxide films: Preparation, characterization and their electrochemical properties

Graphene oxide (GO) film was electrochemically reduced by a cyclic voltammetry technique in 6 mol L-1 KOH aqueous solution.Electrochemically reduced graphene oxide (ER-GO) film was characterized by X-ray diffraction,X-ray photoelectron spectroscopy,atomic force microscopy,and Raman spectroscopy.The oxygen content (with the O/C atomic ratio of 1.29%) was significantly decreased after electrochemical reduction.The ER-GO film exhibited a specific capacitance of 152 F g-1 at the current density of 5 A g-1 and a good rate capability.Furthermore,the ER-GO film showed an excellent cycling ability.The capacitance retention remained 99% after 3000 cycles at the current density of 10 A g-1.     

孔道结构对有序介孔炭电化学性能的影响

以三嵌段共聚物（F127）为模板剂,间苯二酚（R）和甲醛（F）为碳前驱体,在外加的酸性条件下通过自组装的方法制得了F127/RF复合材料,然后经碳化处理得到具有高度有序孔道结构的介孔炭材料（OMCs）,通过XRD、TEM、N₂吸/脱附手段(77K低温下)对其进行结构表征。测试结果表明有序介孔炭材料的BET比表面积和总孔体积分别为770m²/g和0.65cm³/g。以有序介孔炭材料为电极制备超级电容器,对其进行直流恒流充放电测试、循环伏安测试和交流阻抗测试,结果显示在电流密度为0.02A/g时OMC-3比容量为130F/g,100次充放电循环后电容量保持率在99%以上。     

K2FeO4石墨化生物质多孔炭的制备及其电容性能

采用K₂FeO₄浸泡和热处理相结合的方法制备了石墨化柚子皮多孔炭(GSPC). 通过扫描电子显微镜(SEM)、比表面积分析(BET)、X射线衍射(XRD)、X射线光电子能谱(XPS)和拉曼光谱(Raman)对材料的形貌和组成进行表征. 使用循环伏安法(CV)、交流阻抗法(EIS)和恒流充放电法(GCD)研究了GSPC的电容性能. 结果表明:石墨化后材料的比表面积由75.91 m2/g增大到619.78 m2/g,孔容积由0.192 cm3/g增大到0.425 cm3/g;GSPC具有出色的双电层电容性能,在1 A/g的电流密度下,比电容达254 F/g,且具有优异的倍率性能(7 A/g的电流密度下,电容保持率为74%). 此外,GSPC电极在100 mV/s下循环10 000次的比电容没有衰减,具有优异的循环稳定性. 此研究可为开发廉价的高性能生物质炭基材料提供新思路.     

Mangosteen peel-derived activated carbon for supercapacitors

This work reports the effects of activation temperatures on the porous development and electrochemical performance of activated carbons. Herein, activated carbons were prepared from the biowaste of mangosteen peel by using KOH activation at temperatures of 400, 600, and 800 ?°C. The results demonstrate that the specific surface area increases with increasing the activation temperatures in which the well-developed porous structure after KOH activation at 800 ?°C provides the highest specific surface area of 1039 ?m² ?g^?1. At 600 ?°C, the activated carbon delivers the highest specific capacitance value of 182 ?F ?g^?1 ?at a current density of 0.5 ?A ?g^?1 in 3 ?M KOH aqueous electrolyte. This is correlated well with its high micropore fractions (99%). Moreover, it was found that the activation temperature changes the major contribution of oxygen-containing functional group on surface of activated carbon, which is beneficial for the enhancement of the specific capacitance value of activated carbon at the temperature of 600 ?°C. This work suggests that the activation temperature is a key to optimizing the electrochemical performance of activated carbons. Overall, our activated carbons can be considered as a strong candidate for use as electrode materials in supercapacitors.     

Facile construction of novel CoMoO4 microplates@CoMoO4 microprisms structures for well-stable supercapacitors

A simple and controllable strategy has been developed to fabricate CoMoO_4 microplates/CoMoO_4 microprisms(CMCMs) structures on Ni foam via a facile, cost-effective, two-step hydrothermal route. The as-grown 3D architecture exhibited excellent areal capacitance of 4.33 F cm~(-2)at a galvanostatic chargedischarge current density of 50 mA cm~(-2)(6 Ag~(-1)) and outstanding cycle performance with only 2.8%degradation over 6500 cycles in the 3 M KOH solution. The asymmetric all-solid-state supercapacitors based on activated carbon(AC) and CMCMs exhibited much better electrochemical performance than the symmetric counterpart, showing an areal capacitance of 95.22 mF cm~(-2)at the current density of 12 m A cm~(-2)and excellent cycling stability with 92.27% of the initial capacitance after 5000 cycles. These results may provide useful guidelines for materials selection and configuration designs for the novel energy storage devices based on Co Mo O4 components and substrates.     

高力学性能及高导电性的防冻有机水凝胶电解质

由于水凝胶电解质的力学性能差且水在低温下会结冰,限制了水凝胶电解质在储能器件和电子导体方面的应用。加入大豆分离蛋白,以丙烯酰胺和甲基丙稀酰乙基磺基甜菜碱为单体,在二甲基亚砜/H₂O的混合溶液和氯化锂的存在下,通过自由基聚合制备了高力学性能、高导电性的防冻有机水凝胶。其具有良好的电导率(最高37.5 mS/cm)、良好的力学性能(最大应力69 kPa,最大应变762.5%)、优良的韧性和抗疲劳性能,对应变和温度具有良好的响应性、宽的传感窗口及稳定性,具有应用于传感器领域的潜力。另外,所制备的超级电容器在20 ℃和-20 ℃均表现出良好的电化学性能,20 ℃时,0.2 A/g电流密度下,超级电容器的比电容为62.1 F/g,5 A/g 的高电流密度下,比电容仍有30 F/g;同时具有良好的抗冻性能和循环稳定性,-20 ℃时,0.5 A/g电流密度下,超级电容器循环10 000圈后仍能保持20 ℃下容量的92%。     

Preparation of three-dimensional graphene foam for high performance supercapacitors

Supercapacitor is a new type of energy-storage device, and has been attracted widely attentions. As a two dimensional (2D) nanomaterials, graphene is considered to be a promising material of supercapacitor because of its excellent properties involving high electrical conductivity and large surface area. In this paper, the large-scale graphene is successfully fabricated via environmental-friendly electrochemical exfoliation of graphite, and then, the three dimensional (3D) graphene foam is prepared by using nickel foam as template and FeCl3/HCl solution as etchant. Compared with the regular 2D graphene paper, the 3D graphene foam electrode shows better electrochemical performance, and exhibits the largest specific capacitance of approximately 128 F/g at the current density of 1 A/g in 6 M KOH electrolyte. It is expected that the 3D graphene foam will have a potential application in the supercapacitors.     

炭气凝胶微球的物理活化与化学活化比较

以炭气凝胶微球为原料,分别采用CO2和KOH作为活化剂,研究物理活化和化学活化对炭气凝胶微球孔结构和电化学性能的影响差异,探讨CO2和KOH的活化机理。结果表明,CO2和KOH活化均能有效改善炭气凝胶微球的孔结构,比表面积最高可达1 320 m2/g;同时显著提高材料的电化学性能,活化后的比电容最高可为活化前的3倍。结果还表明两种方法的活化机理不同,CO2活化,有利于保持炭气凝胶微球的中孔,为电子进出提供大量的快速通道,提高传质速率;KOH活化,对炭气凝胶微球的微孔形成非常有利,可增大电化学活化表面,提高电化学性能。     

晋城超低灰无烟煤制备高比表面积颗粒活性炭的试验研究

以晋城无烟煤为原料,先经浮选和酸洗脱灰,得到灰分1.2%的超低灰无烟煤,再将其与活化剂KOH按比例混合、粘结成型,并经活化处理制备高比表面积活性炭。主要考查了碱炭比、活化温度和活化时间对活性炭比表面积及收率的影响。结果表明,晋城超低灰无烟煤制备高比表面积活性炭的最佳工艺条件为:碱炭比5∶1,活化温度800℃、活化时间1 h,活性炭的BET比表面积为1 800.71 m2/g,孔径大小分布于0.3～5 nm之间,以微孔为主。     

Preparation of mesoporous MgO-templated carbons from phenolic resin and their applications for electric double-layer capacitors

Mesoporous carbons were synthesized using thermoplastic phenolic resin (PF) as carbonaceous precursor and magnesium citrate as template precursor. Pore structure was determined as ink-bottle-like geometry through TEM, N2 adsorption analysis combined with TG curves. The porous carbons prepared were then applied as electrode material for electric double-layer capacitors. The capacitor performance was examined in 30 wt% KOH aqueous solution by cyclic voltammetry and galvanostatic charge/discharge measurements. The carbon prepared with MgO/PF mass ratio of 8/2 had a BET surface area of 1920 m² g^?1 and exhibited a capacitance of 220 F g^?1 at a current density of 50 mA g^?1. Besides, the carbon with the ratio of 4/6 had the optimize proportion of mesopores, which ensures its good rate performance that up to 98.3%, expressed as the ratio of the capacitance measured at 1000 mA g^?1 against that at 50 mA g^?1.     

复合导电剂在超细炭微球超级电容器中的应用研究

导电剂能否在电极材料中形成良好的导电网络是影响超级电容器性能的关键因素之一. 以改进St?ber法合成了高比表面积且具有多级孔结构的超细空心炭微球,以其为电极材料,对比研究了碳纳米管/炭黑复合导电剂与单一导电剂对基于超细空心炭微球超级电容器性能的影响. 研究发现,在0.2 A/g的电流密度下,采用复合导电剂时其比电容为205.7 F/g,远高于单一导电剂时的比电容. 尤其在100 A/g的大电流密度下,采用复合导电剂时的比电容高达104.0 F/g,相比炭黑导电剂提高了275%. 分析表明,纤维状的碳纳米管和炭黑可在本身易团聚的超细空心炭微球中形成点-线协同作用的导电网络,这是提升超级电容器性能的主要原因.      

表面含氧官能团对活性炭电化学性能的影响

采用浓硝酸对椰壳活性炭和各壳活性炭进行液相氧化改性后，制成了以KOH为电解液的超级电容器的炭电极，研究表面含氧官能团在碱性电解液中对电容器电极的电化学性能的影响．运用低温N2吸附、XPS和FTIR表征活性炭孔结构和表面性质．研究结果表明，氧化后活性炭的比表面积和孔容降低，表面含氧量增大．且经硝酸氧化后炭表面的含氧官能团含量发生了变化，即在内酯基的含量减少的同时，羟基、羰基和菝基的含量增加，其中羟基含量的增幅最大．在50mA／g电流密度下经过100次充放电循环，氧化后的椰壳活性炭和杏壳活性炭质量比电容分别达到193 F/g和150F／g，均比氧化前提高了30％以上．由XPS的分析结果判断，羟基对电极比电容提高的贡献最大．同时，在大电流充放电时，氧化后炭电极的比电容的衰减率明显低于氧化前．