Preparation and Characterization of Antibacterial Polyacrylonitrile-based Activated Carbon Fiber Supporting Nano-ZnO

Polyacrylonitrile(PAN)-based activated carbon fiber(PACF) supporting nano-ZnO(PACF /nano-ZnO) was prepared by spin, pretreatment, carbonization, and KOH chemical activation at an activation temperature of 950 ℃ for 40 min. Nano-ZnO content, distribution and antibacterial properties of the PACF/nano-ZnO were studied. The pore structure and surface properties of the PACF/nano-ZnO were studied by Brunauer-Emmett-Teller(BET), N₂/77 K isothermal adsorption. The specific surface area increased markedly after the activation process and it was several hundred times greater than that before the process. The PACF/nano-ZnO shows a strong adsorption for Staphylococcus aureus(S. aureus) and Escherichia coli(E. coli) and antibacterial activity against them. As an experimental result, antibacterial properties of PACF/nano-ZnO increased with increasing the concentration of nano-ZnO particles, which suggests it is a promising antibacterial material.     

氢氧化钾活化制备超级电容器多孔碳电极材料

具有高比表面积、良好导电性的多孔碳材料在超级电容器中有着广泛的应用前景. 大量的研究工作致力于通过物理或者化学手段合成并调控多孔材料的微观结构. 在众多多孔碳材料的制备方式中,氢氧化钾作为一种高效的活化剂,常用于制备具有良好孔径分布和高比表面积多孔碳电极材料. 本文主要结合作者课题组的研究工作,着重概述利用氢氧化钾活化sp²碳纳米材料制备多孔碳材料的机理过程、结构形貌的转变以及所得材料的电化学性能,希望对发展新型的高性能基多孔碳材料的超级电容器电极材料有所帮助.     

KOH活化木屑生物炭制备活性炭及其表征

以木屑热裂解的生物质炭为原料,氢氧化钾为活化剂,采用化学活化法制备活性炭,探讨了碱炭比、活化温度和活化时间对活性炭吸附亚甲基蓝吸附值的影响。 利用N2吸附实验、XRD和FTIR等实验技术,对原料与制备活性炭的结构与性能进行了表征。 结果表明,在碱炭质量比为1.5、活化温度750 ℃、活化时间2 h的条件下,所制备的活性炭对亚甲基蓝吸附值为255 mg/g,BET总比表面积为1514 m2/g,中孔比表面积为110 m2/g,吸附总孔容为0.821 cm3/g,中孔孔容为0.117 cm3/g,吸附平均孔径为2.170 nm。     

Preparation and Characterization of Activated Carbon Fiber from Paper

Activated carbon fibers (ACFS) with surface area of 1388 m²/g prepared from paper by chemical activation with KOH has been utilized as the adsorbent for the removal of methy-lene blue from aqueous solution. The experimental data were analyzed by Langmuir and Freundlich models of adsorption. The effects of pH value on the adsorption capacity of ACFS were also investigated. The rates of adsorption were found to conform to the kinetic model of Pseudo-second-order equation with high values of the correlation coefficients (R>0.998). The Langmuir isotherm was found to fit the experimental data better than the Feundlich isotherm over the whole concentration range. Maximum adsorption capacity of 520 mg/g at equilibrium was achieved. It was found that pH played a major role in the adsorption process, higher pH value favored the adsorption of MB.     

Activated carbon produced from paulownia sawdust for high-performance CO2 sorbents

In this paper, activated carbons （ACs） with high specific surface areas were successfully synthesized by simple one-step carbonization-activation from paulownia sawdust biomass, and the effects of the synthetic conditions on their CO2 capture capacity were investigated as well. The results show that, when the mass ratio between activator and biomass is 4, the activation temperature is 700℃ and the activation time is 1 h, as-made AC provides the most micropores for CO2 adsorption. As a consequence, the maximum CO2 uptake of 8.0 mmol/g is obtained at 0 ℃ and 1 bar.     

蜂巢状多孔明胶制备高性能超级电容器用活性炭

近年来,以生物质为前驱体来制备碳材料因其资源丰富、廉价易得、无污染且可再生等优点而引起人们的广泛关注。本文将生物质明胶制备成呈蜂巢状的多孔结构,并以此为前驱体经碳化、活化制备活性炭。研究表明,与商品化明胶相比,由多孔明胶所制备的活性炭其比表面积(可高达3692 m~2?g1)及超级电容器性能均有明显提升。在6 mol?L~(-1) KOH水溶液中,由多孔明胶经600°C碳化、700°C KOH活化所制备的活性炭,在1 A?g~(-1)的放电容量为357 F?g~(-1),即使在100 A?g~(-1)的大电流密度下,其比电容仍可维持在227 F?g~(-1)。活性炭样品也表现出优异的循环稳定性,在10 A?g~(-1)下经7500圈循环稳定性测试后,其初始容量保持率高达93.0%。而且,以该活性炭组装的对称型超级电容器,在250、2500及25000 W?kg~(-1)的功率密度下,其能量密度分别为10.3、9.7和8.2 Wh?kg~(-1);在10 A?g~(-1)下经10000次循环后,容量保持率高达97.6%。这些研究结果表明由蜂巢状多孔明胶所制备的活性炭在高性能超级电容器中具有巨大的应用潜力。     

染料在剑麻基活性碳纤维上吸附速度的研究

本文研究了单组分染料在活性碳纤维上的吸附速度及双组分染料的竞争吸附速度。研究结果表明,不同染料分子在ＳＡＣＦ上吸附速度差异较大,结晶紫的吸附速度比亚甲基蓝或铬蓝黑Ｒ慢行多。亚甲基蓝和铬蓝黑Ｒ双组分共存时,其吸附速度与单组分时的相近,但初始阶段亚甲基蓝的吸附比铬蓝黑Ｒ快得多。由于染料的分子尺寸与ＡＣＦ的微孔大小相近,染料在活性碳纤维上的七染料孤及活怀碳纤维的孔结构密切相关。因此,不同染料分子在ＡＣＦ     

氧化还原活性碳纤维的研究进展

就氧化还原碳纤维的制备及其结构、影响氧化还原容量的因素、氧化还原机理等方面进行了综述，并做了研究前景展望。     

萘在粘胶基活性炭纤维上的吸附

研究了水溶液中萘在粘胶基活性炭纤维(VACF)吸附剂上的等温吸附.用多种吸附方程(Langmuir、Freundlich、Dubinin-Radushkevitch(D-R)、Dubinin-Astalov(D-A)、Langmuir-Freundlich(L-F)、Redlich-Peterson(R-P))对吸附实验数据进行拟合,考察了温度、pH和负载铜离子对萘吸附的影响.方程拟合结果表明微孔吸附容积填充理论对VACF吸附萘有较好的适用性,优于单层吸附理论.在20-40℃之间,萘的吸附是自发进行的,30℃以上时,萘的吸附量显著降低.提出了新的机理来解释pH较低时吸附量显著上升的实验现象.负载铜离子后VACF对萘吸附量降低.     

Enhanced Capacitive Characteristics of Activated Carbon by Secondary Activation

The effect of the improvement of commercial activated carbon(AC) on its specific capacitance and high rate capability of double layer(dl) charging/discharging process has been studied. The improvement of AC was carried out via a secondary activation under steam in the presence of catalyst NiCl2, and the suitable condition was found to be a heat treatment at about 875 ℃ for 1 h. Under those conditions, the discharge specific capacitance of the improved AC increases up to 53. 67 F/g, showing an increase of about 25% as compared with that of as-received AC. The good rectangular-shaped voltammograms and A.C. impedance spectra prove that the high rate capability of the capacitor made of the improved AC is enhanced significantly. The capacitance resistance (RC) time constant of the capacitor containing the improved AC is 1.74 s, which is much lower than that of the one containing as-received AC(an RC value of 4. 73 s). It is noted that both kinds of AC samples show a similar specific surface area and pore size distribution, but some changes have taken place in the carbon surface groups, especially a decrease in the concentration of surface carbonyl groups after the improvement, which have been verified by means of X-photoelectron spectroscopy. Accordingly, it is suggested that the decrease in the concentration of surface carbonyl groups for the improved AC is beneficial to the organic electrolyte ion penetrating into the pores, thus leading to the increase in both the specific capacitance and high rate capability of the supercapacitor.     

四元Mg0.9Ti0.1Ni0.9X0.1(X=Mn,Zn,Co,Fe)系列合金的制备及性能研究

用机械合金化法合成了Mg0.9Ti0.1Ni0.9X0.1(X=Mn,Zn,Co,Fe)系列合金.X射线衍射(XRD)结构分析表明,用X部分替代Ni后,促进了Mg0.9Ti0.1Ni合金的非晶化过程.用Co和Fe部分替代Ni提高了合金的放电容量,但却降低了合金的循环稳定性.用Zn和Mn部分替代Ni提高了合金电极的循环寿命,尤其是Mg0.9Ti0.1Ni0.9Zn0.1合金电极经10个充放电循环后,其放电容量仍可达到313.8mA.h/g.对添加Co后的合金进行p-c-T测试发现,Mg0.9Ti0.1Ni0.9Co0.1合金的吸放氢容量明显比Mg0.9Ti0.1Ni合金高,这与电化学所测到的结果一致.     

聚苯胺/活性碳复合型超电容器的电化学特性

电化学电容器作为一种新型储能器件具有广泛的应用.采用(NH₄)₂S₂O₈化学氧化聚合苯胺法制备了聚苯胺电极材料，采用化学物理二次催化活化法制备了高比表面积活性碳材料.并用循环伏安、恒流充放电以及交流阻抗等方法对上述电极材料的电化学特性进行了研究.实验结果表明,所制备的聚苯胺电极材料具有高于420 F•g^－1的法拉第赝电容和良好的电化学特性，所制备的活性碳电极材料则具有160 F•g^－1的双电层电容量.分别采用聚苯胺作为正极，活性碳作为负极，38％硫酸作为电解液制备了复合型电化学电容器.复合型电容器工作电压达到1.4 V, 电容器单体比电容达到57 F•g^－1，最大比能量和最大真实比功率分别达到15.5 W•h•kg^－1和2.4 W•g^－1, 峰值比功率达到20.4 W•g^－1,电容器循环工作寿命超过500次. 与活性碳双电层电容器相比，复合型电容器还具有较低的自放电率.     

KOH活化糠醛渣制备活性炭机理与表征

以糠醛渣为原料、KOH为活化剂,采用两步活化法制备了活性炭。考察了活化温度、活化时间、碱炭比和浸渍时间对活性炭孔结构及吸附性能的影响。采用低温N2吸附、BET、BJH及DFT理论对活性炭孔结构进行了表征分析,利用傅里叶变换红外-拉曼光谱仪检测其表面官能团,分别使用扫描电镜和X射线衍射对其进行表观形貌观察和晶型分析。结果表明,制备活性炭的最佳工艺条件为:活化温度800℃、活化时间3h、碱炭比3∶1、浸渍时间12h。所制备的糠醛渣活性炭的吸附孔径分布集中,吸附孔容为0.8825cm2/g,DFT总比表面积为3290.5m2/g,其碘吸附值和亚甲基蓝吸附值分别为2107.32mg/g和39.67mL/0.1g。     

电解质浓度和温度对活性炭电容性能的影响

采用循环伏安、交流阻抗和恒流充放电技术考察了电解质浓度和温度对活性炭电容性能的影响. 活性炭电容器在0.1、0.5、1.0和6.0 mol·L^-1 KOH溶液中性能测试结果表明: 活性炭在高浓度电解质中具有高电容和低内阻, 但电位窗口较窄; 电容和内阻与KOH浓度的对数成正比. 活性炭电容在不同温度(20、40、80 °C)的性能测试结果表明: 高温能够增加电容和降低内阻, 但是却加速了长期充放电过程中电容的衰减.     

H3PO4/KOH Activation Agent for High Performance Rice Husk Activated Carbon Electrode in Acidic Media Supercapacitors

H₃PO₄/KOH combined solution is proposed as a new effective activation agent for activated carbon production from rice husk. Several activated carbon samples were produced by using different volumes of the utilized acid and alkali individually, in addition to the combined solution. FTIR results indicated that the mixed agent partially decomposed the chemical compounds on the rice husk char surface, resulting in an increase in the surface area. Moreover, XRD and EDS analyses showed the presence of a considerable amount of amorphous silica. Electrochemical measurements concluded that the volume of the activation agent solution should be optimized for both single and mixed activation agents. Numerically, for 0.3 g treated rice husk char, the maximum specific capacitance was observed at 7, 10 and 14 mL of H₃PO₄, KOH (3 M) and mixed (1:1 by volume) activation agents, respectively; the determined specific capacitance values were 73.5, 124.2 and 241.3 F/g, respectively. A galvanostatic charging/discharging analysis showed an approximate symmetrical triangular shape with linear voltage versus time profile which indicates very good electrochemical performance as an electrode in the supercapacitors application. The stability of the proposed activated carbon was checked by performing a cyclic voltammetry measurement for 1000 cycles at 2 mV/s and for 30,000 cycles at 10 mV/s. The results indicate an excellent specific capacitance retention, as no losses were observed.     

活性炭基软包装超级电容器用有机电解液

使用了一种新型的有机电解液(三乙基甲基四氟硼酸铵/(丙烯碳酸酯+乙腈): MeEt₃NBF₄/(AN+PC))和两种传统有机电解液(四乙基四氟硼酸铵/丙烯碳酸酯(Et₄NBF₄/AN)和四乙基四氟硼酸/乙腈(Et₄NBF₄/PC)), 制作成活性炭(AC)基软包装超级电容器. 在不同电压窗口下对新型有机电解液的循环伏安和电化学阻抗谱进行了表征, 并在0-3 V的电压窗口下, 通过循环伏安、电化学阻抗谱、恒流充放电、漏电流、自放电、循环寿命和库仑效率, 对以上三种电解液进行了综合的比较. 结果表明, 新型有机电解液综合了AN和PC各自的优点, 性能优异.     

活性炭表面担载氧化锰复合电极的电化学电容性能

通过在两种商品活性炭XC-72(比表面250m2·g-1)和YEC-8(比表面1726m·2g-1)电极表面涂刷Mn(NO3)2,并在200℃进行热分解得到表面担载氧化锰的复合材料电极.采用扫描电子显微镜(SEM)和X射线衍射(XRD)表征电极的形貌和氧化锰的晶体结构,采用循环伏安、恒流充放电和交流阻抗考察了不同电极的电化学电容性能.结果表明,Mn(NO3)2在200℃的热解产物是α-Mn2O3和α-Mn3O4的混合物.当C和MnOx的质量比为2∶1和9∶1时,XC-72/MnOx中氧化锰的比电容分别达到499和435F·g-1,YEC-8/MnOx中氧化锰的比电容分别达到554和606F·g-1,表明氧化锰的赝电容对电极比电容的贡献十分显著.     

One‐stage Template‐free KOH Activation for Mesopore‐enriched Carbons and Their Application in CO2 Capture

Activated carbons with a high mesoporous structure were prepared by a one‐stage KOH activation process without the assistance of templates and further used as adsorbents for CO₂ capture. The physical and chemical properties as well as the pore structures of the resulting mesoporous carbons were characterized by N₂ adsorption isotherms, scanning electron microscopy (SEM ), X‐ray diffraction (XRD ), Raman spectroscopy, and Fourier transform infrared (FTIR ) spectroscopy. The activated carbon showed greater specific surface area and mesopore volume as the activation temperature was increased up to 600°C, showing a uniform pore structure, great surface area (up to ~815 m²/g), and high mesopore ratio (~55%). The activated sample exhibited competitive CO₂ adsorption capacities at 1 atm pressure, reaching 2.29 and 3.4 mmol/g at 25 and 0°C, respectively. This study highlights the potential of well‐designed mesoporous carbon as an adsorbent for CO₂ removal and widespread gas adsorption applications.     

含磷活性炭作为双电层电容器电极材料的电化学性能

采用磷酸活化和磷酸改性制备了不同种类的含磷活性炭,采用元素分析、X射线光电子能谱(XPS)和氮气吸附等手段分析了活性炭的元素含量、表面化学性质和孔隙结构,采用恒电流充放电、循环伏安和交流阻抗分别考察了活性炭在KOH和H₂SO₄电解质溶液中作为超级电容器电极材料的电化学性能,采用自由截距多元线性回归拟合统计分析研究了活性炭电极比电容量的影响因素,应用三电极体系分析了磷元素对活性炭电化学性能的影响机理。研究结果表明,活性炭掺杂的磷引入了赝电容,提高了活性炭电极的比电容量,磷元素含量为5.88%(w)的活性炭的比电容量在0.1 A·g^-1下达到185 F·g^-1。统计分析结果显示,活性炭的中孔有利于电解质离子向微孔内的扩散。在6 mol·L^-1 KOH电解质溶液中,孔径在1.10-1.61 nm、2.12-2.43nm及3.94-4.37 nm范围内是电解质离子在活性炭孔隙内部形成双电层的主要场所;在1 mol·L^-1 H₂SO₄电解质溶液中,孔径在0.67-0.72 nm范围内有利于双电层电容的形成。     

微波辐射技术在活性炭制备中的应用

对微波辐射技术在活性炭的活化、表面改性及再生过程中的研究进展进行了概述。微波功率是影响活性炭的活化、改性、再生及其吸附性能和得率的主要因素之一。众多实验结果表明,微波辐射技术是制备活性炭材料和提高活性炭吸附性能的有效途径。