Ali A. ENSAFI*
,
Hajar BAHRAMI
,
0Hassan KARIMI-MALEH
,
Shadpour MALLAKPOUR
催化学报
doi:10.1016/S1872-2067(11)60465-8
A carbon paste electrode with added multiwall carbon nanotubes chemically modified with N-(3,4-dihydroxyphenethyl)-3,5-dinitrobenzamide was used as the electrochemical sensor for the determination of trace amounts of isoprenaline. The modified electrode showed good electrocatalytic activity for the anodic oxidation of isoprenaline, which was due to a substantial decrease in the anodic overpo-tential. Under the optimum conditions, measurements using square wave voltammetry had a linear range in the range of 0.3 to 125.0μmol/L of isoprenaline and a detection limit of 0.1μmol/L. The diffusion coefficient and kinetic parameters were determined using electrochemical methods. The relative standard deviation for seven successive assays of 1.0 and 20.0μmol/L isoprenaline were 1.9% and 2.4%, respectively. This electrochemical sensor was successfully applied for the determination of isoprenaline in human urine and injection solution samples.
关键词:
isoprenaline
,
carbon nanotube
,
electrode
,
electrocatalytic effect
,
voltammetry
Y.Li
金属学报(英文版)
Two carboxylation processes were carried out to modify multi-walled carbon nanotube bundles (m-MWNTs). The results showed that both of the m-MWNTs could be highly dispersed in water with the concentration up to 25 and 15mg/mL in ethanol without obvious deposition or conglomeration over 6 months. FTIR, Raman, TGA and TEM characterizations of the m-MWNTs showed that hydroxyl and carboxyl groups have been attached with MWNTs, and that the nanotube structure was only damaged a little after modification treatments in mixed acids over 24h. Above prepared nanotube suspensions in water were successfully used as a filler of thermoplastic PVA composite to enhance its electrical conductivity. The results showed that the addition of m-MWNTs greatly improved the conductivity and the threshold of mass fraction was about 5wt The results also proved that purification process was not needed because of high ouritv of the raw MWNTs oreoared in our group.
关键词:
carbon nanotube
,
null
,
null
C.G.Hu
,
W.L.Wang
,
K.J.Liao
,
W.Zhu
金属学报(英文版)
The electrochemical behavior of a carboxyl-modified carbon nanotube films was inves-tigated to explore its possibility in electroanalytical applicaton. Cyclic voltammetry of quinone was conducted in 1mol/L Na2SO4, which showed a stable, quasi-reversible voltammetric response for quinone / hydroquinone, and the anodic and the cathodic peak potentials were 0.657V and -0.029V (vs. SCE) at a scan rate of 0.1V.s^-1, re-spectively. Both anodic and cathodic peak currents depended linearly on the square root of the scan rate over the range of 0.01-0.5V.s^-1, which suggested that the process of the electrode reactions was diffusion-controlled. Carboxyl-modified carbon nanotube electrodes made it possible to determine low level of dopamine selectively in the pres-ence of a large excess of ascorbic acid in acidic media using derivative voltammetry.The results obtained were discussed in details. This work demonstrates the potential of carboxyl-modified carbon nanotube electrodes for electroanalytical applications.
关键词:
carbon nanotube
,
null
,
null
张强
,
赵梦强
,
黄佳琦
,
骞伟中
,
魏飞
催化学报
通过浸渍及水热处理获得MgO负载的Fe基催化剂,并将其用于化学气相沉积过程裂解甲烷获得碳纳米管. 结果表明,单/双/多壁碳纳米管可选择性地生长在Fe负载量不同的Fe/MgO催化剂上. 当Fe负载量仅为0.5%时,铁原子在载体表面烧结为0.8～1.2 nm的铁颗粒,碳在这种小颗粒上以表面扩散为主,导致单壁碳纳米管形成,并且单壁碳纳米管的选择性高达90%. 当Fe负载量提高到3%时,铁原子聚集成约2.0 nm的颗粒,在化学气相沉积中生长碳纳米管时,碳在Fe催化剂颗粒中的体相扩散的贡献增大,在表相扩散和体相扩散的共同作用下,双壁碳纳米管的选择性显著增高. 当进一步增加Fe负载量时,铁原子烧结形成1～8 nm的颗粒,经过化学气相沉积,在催化剂上生长了单、双、多壁碳纳米管. 随着Fe在MgO载体上负载量的增加,管径、管壁数以及半导体管的含量都增加. 本研究提供了一种适合大批量选择性生长单/双/多壁碳纳米管的方法.
关键词:
碳纳米管
,
化学气相沉积
,
铁
,
氧化镁
,
负载型催化剂
,
微结构
,
拉曼光谱
于素霞
,
杨建华
,
初乃波
,
李刚
,
鲁金明
,
王金渠
催化学报
以经盐酸预处理的碳纳米管为第二模板,在不添加其它有机溶剂的情况下,仅通过控制晶化条件,即采用变温水热晶化法合成具有多级结构的ZSM-5分子筛.通过x射线衍射、红外光谱测试、透射电镜和N2吸附对合成的分子筛进行了表征,结果表明,该合成分子筛呈近球形,是由纳米棒自组装形成的具有多级结构的亚微米球.该分子筛改性后用于甲烷无氧脱氢芳构化反应,显示出良好的催化性能,甲烷转化率最初达到19%,反应至24 h时甲烷转化率仍保持在10%左右,并且保持了较高的芳香物选择性(达到50%以上).
关键词:
多级结构
,
ZSM-5沸石
,
水热晶化
,
碳纳米管
,
钼催化剂
,
甲烷
,
无氧脱氢芳构化
周春梅
,
王红娟
,
梁家华
,
彭峰
,
余皓
,
杨剑
催化学报
制备了一种新的甲醇直接燃料电池Pt/RuO2/CNTs阳极催化剂,在相同Pt负载量下,其甲醇电催化氧化活性是Pt/CNTs的3倍. 采用循环伏安法研究发现Pt/RuO2/CNTs纳米催化剂中RuO2含量对甲醇电催化氧化活性有明显影响,当Pt和RuO2在碳纳米管上含量分别为15%和9.5%时, Pt/RuO2/CNTs催化剂具有最佳的甲醇电催化氧化活性. RuO2负载在碳纳米管上比电容的变化,反映了水合RuO2结构中质子与电子传输平衡的能力,分析表明,催化剂中RuO2含量不同导致电容的变化是影响甲醇电催化氧化活性的主要原因. 当催化剂结构中质子与电子传输达到平衡时,催化剂比电容最大,电催化氧化活性最高. 这种基于电容关联电催化剂的观点对甲醇直接燃料电池阳极催化剂的设计非常有意义.
关键词:
铂
,
氧化钌
,
碳纳米管
,
甲醇直接燃料电池
,
阳极催化剂
,
比电容
,
质子传导
姚伟宣
,
应剑波
,
张素玲
,
张春晓
,
王海栋
,
蔡国栋
色谱
doi:10.3724/SP.J.1123.2014.11029
通过化学共沉淀法使Fe3 O4纳米粒子负载于酸化多壁碳纳米管（ AMWNTs）表面，得到Fe3 O4／AMWNTs磁性纳米材料。该材料具有很好的磁响应度和分散性，将其用于富集痕量拟除虫菊酯类农药残留，结果证明该复合材料对菊酯类农药的吸附性能良好。通过对影响萃取性能的几种因素如离子强度、萃取时间和解吸时间依次进行优化，在最优条件下，建立了Fe3 O4／AMWNTs磁性分散固相萃取?气相色谱测定6种菊酯类农药残留的分析方法。线性范围在0?5～50μg／L之间，相关系数（ R2）大于0?990，检出限为0?07～0?20μg／L，精密度为3?8％～8?1％。该方法用于河水、鱼塘水和两种市售蜂蜜中菊酯类农药的残留分析，回收率高于78?4％。该方法操作简便、灵敏度高，能够满足环境水样及蜂蜜样品中痕量菊酯农药残留的分析需求。
关键词:
碳纳米管
,
磁性纳米材料
,
磁性分散固相萃取
,
气相色谱
,
菊酯类农药
,
水
,
蜂蜜
施连伟
,
赵灵智
,
李昌明
材料导报
碳纳米管因具有特殊的结构和独特的物理化学特性而被广泛研究.它优良的嵌锂性能使其可能成为一种优良的锂离子电池材料.单独的碳纳米管作为锂离子电池负极材料,有优点也存在着缺点,将碳纳米管与其他材料复合,利用复合材料中各组分间的协同效应,达到优劣互补,可以大大提高锂离子电池材料的性能.综述了近年来研究者们对碳纳米管及其复合材料在锂离子电池负极材料中的研究进展,并展望了碳纳米管/硅基复合材料的研究前景.
关键词:
锂离子电池
,
负极材料
,
碳纳米管
,
碳纳米管复合材料
刘树和
,
白朔
,
李峰
,
孙可伟
材料导报
主要介绍了CVD碳包覆工艺、包覆层种类和物理性质(结构、含量和分布)对电极材料电化学性能(首次容量、首次库仑效率、循环和倍率充放电性能等)的影响,在此基础上提出了尚需深入研究的问题,并对CVD法碳包覆改性电极材料的发展趋势和前景进行了讨论.
关键词:
锂离子电池
,
电极材料
,
热解炭
,
纳米碳管
,
化学气相沉积
徐强
,
曾效舒
,
徐耀勇
,
袁秋红
机械工程材料
采用机械搅拌铸造法制备了包覆镍碳纳米管(CNTs)/AM60复合材料,研究了包覆镍CNTs加入量对铸态复合材料力学性能的影响规律,并用扫描电子显微镜观察了复合材料的拉伸断口形貌以及显微组织.结果表明:复合材料显微组织为等轴晶,包覆镍的CNTs主要分布在α-Mg共晶相内和晶界处,不仅起到细化晶粒的作用,而且还起到搭接晶粒和强化晶界的作用;复合材料的力学性能随CNTs加入量的增多呈现先增大后减小的趋势,当其质量分数为1%时,抗拉强度、显微硬度、伸长率同时达到最大,比AM60镁合金分别提高了46.23%,41.82%,74.52%,弹性模量在其质量分数为1.2%时达到最大.
关键词:
AM60镁合金
,
碳纳米管
,
复合材料
,
显微组织
,
力学性能
