不同成型工艺对纳米碳管电极电吸附脱盐性能的影响

分别采用酚醛树脂(PR)为粘结剂热压和聚四氟乙烯(PTFE)为粘结剂冷压的成型工艺制备电吸附脱盐器的纳米碳管(CNTs)电极,利用氮气吸附分析电极表面结构,结果表明热压成型电极比表面积较大,所形成的孔隙基本为中孔,平均孔径大于盐水中水合Na+和Cl-的有效半径;结合扫描电镜(SEM)和水珠接触角测试分析,发现热压成型电极表面空隙丰富,亲水性强;进行充放电测试,发现热压成型电极电吸附性能显著优于冷压成型电极,故热压成型纳米碳管电极脱盐性能优越.     

炭化处理对纳米碳管电极电吸附脱盐性能的影响研究

利用酚醛树脂粘结剂压制纳米碳管电极片,组成电吸附脱盐器,对电极片炭化处理前后,电吸附脱盐器的充放电性能和脱盐效果作了比较,发现电极片经炭化后,电极片比表面积大大增加,表面空隙增多,亲水性能提高,其充放电性能和脱盐效果有了显著改善.     

纳米碳管与活性炭复合电极电吸附脱盐性能的研究

为考察纳米碳管（CNTs）、活性炭（AC）及其复合电极的电吸附脱盐性能，将其粉末压制成电极，组装成脱盐器，比较电极电吸附脱盐能力和脱盐能耗。结果表明，在活性炭电极中添加纳米碳管有效地降低了电极电阻和脱盐能耗，少量纳米碳管的添加能在一定程度上提高其电极比表面积、孔容以及在盐水中的比电容；当复合电极中纳米碳管的含量为10％时，其电极在盐水中的电吸附比电容达到113.5F/g，其电极脱盐效果最为显著，其脱盐耗能比活性炭电极降低约67％左右。     

多壁纳米碳管电极电吸附脱盐性能的研究

利用透射电镜(TEM)和X射线衍射(XRD)对多壁纳米碳管形貌和晶型结构进行分析,发现多壁纳米碳管管径分布范围窄,其层间距大于高定向石墨,且随着管径的增大逐渐减小;利用多壁纳米碳管对氮气吸附实验分析其表面结构,发现其比表面积和孔容随管径的增大而减小,所形成的空隙绝大部分为中孔;将多壁纳米碳管处理后,压制成电极,组装成电吸附脱盐器,研究纳米碳管管径对电极电容和脱盐性能的影响,结果表明多壁纳米碳管管径越小,电极比电容越高,脱盐能力越强,随着中孔比表面积增大电极比电容和电极单位脱盐量均呈线性增加。     

液流式电容型脱盐器纳米碳管电极的研究

将纳米碳管压制成电极,组装成液流式电容型电吸附脱盐器。经测试发现纳米碳管电极性能稳定,在盐水溶液中等效电阻小,约为2．4Ω;纳米碳管电极比脱盐量与盐水初始浓度之间存在如下关系：Wdesal=0．18C^1/3;在液流式电吸附脱盐器中,纳米碳管电极具有良好的稳定性和较长的使用寿命。     

纳米碳管电吸附氯化钠性能的研究

将纳米碳管制成电极,研究端电压、氯化钠溶液流量、氯化钠溶液初始浓度、纳米碳管管径对纳米碳管电极电吸附氯化钠性能的影响,结果表明:纳米碳管电极最佳脱盐的端电压和氯化钠溶液流量分别为2.0V和10mL/min,并且纳米碳管电极脱盐与纳米碳管的比表面积和氯化钠溶液初始浓度有关,在大量的实验数据上,得出了电极脱盐方程为ηdes...     

纳米碳管块状电极成型方法的研究进展

概述了当前纳米碳管块状电极成型方法的研究现状,介绍了直接高温热压成型方法、以聚四氟乙烯(PTFE)和聚偏氟二乙烯(PVDF)为粘结剂的冷压粘结成型方法和以酚醛树脂(PR)为粘结剂的热压粘结成型方法,并对冷压粘结成型和热压粘结成型方法进行了比较,提出了适合液流式电容型脱盐电极的成型方法.     

纳米碳管/活性炭复合电极苦咸水淡化的研究

通过对活性炭的N2吸附发现:活性炭具有高的比表面积和大的孔容,适合用于脱盐,但是其存在能耗大并且强度低等缺点.而纳米碳管是一种低电阻率,高强度的新型材料,采用活性炭复合纳米碳管,可以结合两者的优点,开发出一种低能耗、高脱盐率的复合电极.对各种复合比例的复合电极脱盐和能耗的测试发现:当纳米碳管的质量比占电极的10%时,脱盐量、能耗和强度达到最佳工艺,并且将该复合电极片数增大的测试发现:该电极脱盐效果好,在循环周期的大部分时间内以脱盐为主,脱盐率超过95 %.     

不同工艺对活性炭电吸附脱盐性能的影响

以活性炭为电极材料是利用电吸附脱盐的重点.以热解法制备了活性炭,采用酸处理及二次活化处理活性炭,并将二次活化的活性炭利用不同的工艺制成电极.研究表明:二次活化法能够使活性炭获得更高的比表面积和更大的孔容,热压和炭化结合的工艺使活性炭电极有着高的比表面积和高的孔容,适合用于苦咸水脱盐.因此,活性炭具有脱盐效果好,脱附时间短,脱盐率达到90%,是一种优良的脱盐电极材料.     

集成纳米碳管电极的电化学检测性能

电极的机械稳定性对电极电化学检测性能的长期稳定性非常重要.利用微波等离子体化学气相沉积法在玻璃基板上集成了纳米碳管电极,并利用该电极对溶液中的邻苯二酚进行了电化学检测.结果表明,经氧等离子体处理的纳米碳管电极具有良好的电化学检测性能,且由于该电极直接集成在玻璃基片上,良好的结构稳定性赋予该电极极为优异的重现性和长期稳定性.     

纯化处理对碳纳米管脱盐性能的影响

利用未经纯化处理和纯化处理后的碳纳米管分别压制成电极片并分别组装成脱盐器,对两种脱盐器的脱盐性能进行了测试,并且利用氮气吸附-脱附、透射电子显微镜、原子力显微镜、拉曼光谱及接触角测试仪等表征手段测试了影响电极脱盐性能的主要性能参数.研究表明,纯化处理使得碳纳米管电极的比表面积大大增加,孔径结构得到了很大的改善,并且含氧官能团的引入使得浸润性能得到了大大的提高,其脱盐性能得到很大改善.     

粘结剂对块状极板碳纳米管双电层电容器性能影响研究

碳纳米管具有良好的导电性和合适的双电层形成区,适于制作双电层电容器极板． 不同粘结剂的使用会影响电容器的性能,分别选用酚醛树脂和聚四氟乙烯（ＰＴＦＥ）作为碳纳米 管极板的粘结剂,在有机电解质溶液中,研究其电容性能与比表面积和极板结构的关系,从而 找出合适的碳纳米管极板粘结剂．     

多壁碳纳米管对钛基二氧化铅电极电化学性能的影响

为提高钛基二氧化铅电极的电化学性能,利用直流电沉积法制备了多壁碳纳米管(MWCNTs)掺杂改性的电积锌用钛基二氧化铅复合阳极材料。通过XRD、SEM等测试方法,研究了不同多壁碳纳米管添加量对电极活性层的物相组成、微观形貌的影响规律。结果显示:掺杂MWCNTs后,在与PbO_2共沉积过程中会阻碍PbO_2的连续生长,使PbO_2晶体细化,同时MWCNTs的引入使得PbO_2晶体在(301)晶面发生了明显的择优生长。电化学测试表明,与纯Ti/β-PbO_2电极材料相比,Ti/β-PbO_2/CNTs电极材料具有更好的电化学性能,当MWCNTs的添加量为3.0g/L时,电极的析氧过电位为1.566 V,降低了0.054 V;自腐蚀电流密度为5.225×10-6A/cm2,降低了8.095×10-6A/cm2,电极的电催化活性和耐腐蚀性能得到改善。     

Experimental Evidence of Rapid Water Transport through Carbon Nanotubes Embedded in Polymeric Desalination Membranes

As water molecules permeate ultrafast through carbon nanotubes (CNTs), many studies have prepared CNTs‐based membranes for water purification as well as desalination, particularly focusing on high flux membranes. Among them, vertically aligned CNTs membranes with ultrahigh water flux have been successfully demonstrated for fundamental studies, but they lack scalability for bulk production and sufficiently high salt rejection. CNTs embedded in polymeric desalination membranes, i.e., polyamide thin‐film composite (TFC) membranes, can improve water flux without any loss of salt rejection. This improved flux is achieved by enhancing the dispersion properties of CNTs in diamine aqueous solution and also by using cap‐opened CNTs. Hydrophilic CNTs were prepared by wrapping CNT walls via bio‐inspired surface modification using dopamine solution. Cap‐opening of pristine CNTs is performed by using a thermo‐oxidative process. As a result, hydrophilic, cap‐opened CNTs‐embedded polyamide TFC membranes are successfully prepared, which show much higher water flux than pristine polyamide TFC membrane. On the other hand, less‐disperse, less cap‐opened CNTs‐embedded TFC membranes do not show any flux improvement and rather lead to lower salt rejection properties.     

Tailoring Thickness of Conformal Conducting Polymer Decorated Aligned Carbon Nanotube Electrodes for Energy Storage

Aligned Carbon nanotubes (A‐CNT) based electrodes have emerged as high‐performance elements in electric energy storage and conversion devices. Morphological tailoring of conformal coatings of poly(ethylenedioxythiophene) (PEDOT) conductive polymer (CP) on the A‐CNT scaffold is demonstrated by controlling CP thickness at the nm scale. Results show that the CP nano‐films dominate the electrode capacitance in a supercapacitor application, contributing as much as 10x (pseudo)capacitance over the electric double layer of pristine A‐CNT due to volumetric vs. surface charge storage. Comparison to theoretical ion mobilities shows that the conformal CP films have active sites at ∼30% doping, indicating the CP quality is similar to thin films on flat substrates and that all these sites are accessed at all CP thickness values (up to 10 nm PEDOT thickness) and do not limit the rate of ion transport in and out of the CP film volume. Supercapacitor electrodes fabricated from these novel morphology‐controlled nanostructured composites provide a new route towards high‐performance next generation energy storage devices.     

Optimization of Conditions for Preparation of Carbon Origin Solid Electrodes Modified with Carbon Nanotubes

A multi-walled carbon nanotubes (MWCNTs) were used for modification of two solid electrode types, glassy carbon electrode (GC), which is widely used for modification in electroanalysis, and, for the first time, paraffin impregnated graphite electrode (PIGE). The optimization of MWCNT/PIGE and MWCNT/GC electrodes was carried out by altering ultrasonication parameters (ultrasonication time, ultrasound generator performance, and dispersing agent). The preparation of modified electrodes was investigated. The most electrochemically sensitive MWCNT/GC electrode was prepared with nanotubes sonicated for 30 min and the most sensitive MWCNT/PIGE for 20 min, both using ethanol/water solution as dispersing agent and 500 W ultrasound generator performance. Both electrodes were successfully used for analysis of lead performed by DC voltammetry. Current responses were measured for the concentration of lead (II) in range from 1 × 10^?5 to 5 × 10^?5 mol dm^?3 for MWCNT/PIGE and also MWCNT/GC electrode.