基于双层微结构的碳纳米管柔性应变传感器的研究

设计了一种具有双层微结构的柔性压阻式应变传感器,并进行了制备方法研究。通过在半固化的环氧树脂基底(Ecoflex~? 00-30)表面制备形成碳纳米管(MCNTs)/环氧树脂(Ecoflex~? 00-30)复合薄膜,用毛刷制备微结构。通过测试分析可得,该柔性应变传感器具有高度可拉伸性能,可承受200%的应变,在0～80%,80%～170%,170%～195%的应变区间,GF值分别为10.5,40.5,190.5。将传感器进行可穿戴运动监测测试,可验证本传感器既可以实现手指和手腕运动等大动作应变的监测,输出电阻值相对变化达到7.5倍;也可以监测肌肉形变弯曲等小应变,输出电阻值相对变化达到1.4倍。     

碳纳米管在生物传感器中的应用

碳纳米管是一种新型的纳米材料,将其用于修饰电极,可以降低化学物质氧化还原反应的过电位,改善生物分子氧化还原可逆性,其大比表面积有利于酶的固定化,还能促进酶活性中心与电极表面的电子传递.碳纳米管的这些特性对于提高生物检测的灵敏度和稳定性具有重大意义,为生物传感器领域开辟了广阔的前景.     

基于碳纳米管微传感器阵列和随机共振的气体检测方法研究

提出了一种基于多壁碳纳米管微传感器阵列和非线性随机共振算法的新型气体检测方法。微传感器阵列包括碳纳米管阳极传感器和碳纳米管阴极传感器以减小检测系统的交叉灵敏度。实验检测了乙醇、丙酮和氨气三种气体,传感器阵列响应输入随机共振系统进行处理,结果表明,信噪比曲线参数能够标定气体浓度和种类,且随机共振处理方法可以有效的降低系统的交叉灵敏度,检测系统具有较好的灵敏度和重复性,具有较好的实用价值。     

碳纳米管/PDMS复合材料柔性阵列压力传感器制备与实验

以碳纳米管（CNTs）作为导电填料,聚二甲基硅氧烷（PDMS）为基体材料,采用溶液法制备出CNTs/PDMS导电复合材料。研究了碳纳米管浓度对复合材料的电学特性和压阻特性的影响规律,得到碳纳米管在PDMS中的渗滤区域。通过复合材料的压力灵敏度优化碳纳米管浓度。以制备的复合材料为敏感材料,FPCB工艺加工的柔性基板为电极,设计制备了一种简单结构和工艺的柔性阵列压力传感器。用零电势法设计了阵列电阻读出电路与LabVIEW实现的上位机配合,实现信号读取和显示。最后通过一个应用实例表明,该柔性阵列压力传感器及信号处理系统可以实现压力分布与大小的实时监测,可为柔性阵列压力传感器设计与制备提供参考。     

羟基--碳纳米管气体传感器气敏性的仿真研究

采用羟基修饰后的碳纳米管作为气体传感器的气敏材料,会使其响应灵敏度提高。利用密度泛函理论研究了两种气体分子（ Cl2和H2 S）在本征单壁碳纳米管（ SWCNT）和羟基修饰过的单壁碳纳米管（ SWCNT—OH）上的吸附。分析其态密度图,并尝试改变气体分子在碳纳米管上的吸附位置与方向,从吸附能的大小、电荷转移量的多少、吸附距离的远近上,为本征SWCNT,SWCNT—OH的气敏性和两种气体在碳纳米管上的最佳吸附位置姿态提供对比与理论分析。     

基于纳米材料的气体传感器的研究进展

简要地概括了气体传感器的工作原理和主要特性,并着重介绍了纳米金属氧化物气体传感器、纳米金属颗粒气体传感器、有机高分子气体传感器和碳纳米管气体传感器这4种气体传感器的工作原理、研究进展以及发展动向。简要地揭示了纳米气体传感器的不足之处,并阐释了这几种纳米气体传感器的未来发展趋势。     

碳纳米管修饰酶生物传感器的应用进展

很多酶生物传感器是利用氧化酶将底物氧化,同时产生过氧化氢,通过在电极表面检测过氧化氢的量来达到检测的目的。碳纳米管用于修饰电极,可降低化学物质氧化还原反应的过电位,改善生物分子氧化还原可逆性,达到提高检测的灵敏度和稳定性的目的。本文介绍了酶生物传感器及碳纳米管修饰酶生物传感器,并综述了近几年来碳纳米管修饰酶生物传感器的应用进展。     

基于单壁碳纳米管的压阻式柔性传感器

一维纳米材料与微结构结合的纳器件制造过程,实现了微纳加工工艺上的创新升级,有可能突破微米级器件的性能极限。首先利用传统的硅微加工技术,在综合性能优异的聚酰亚胺PI(Polyimide)薄膜上制作金(Au)微电极,形成排列有序的平行电极对;然后通过交流介电电泳的方法在微电极对间实现单壁碳纳米管SWNTs(Single-Walled Carbon Nanotubes)一维定向排布;接着采用区域选择性电沉积技术定域沉积Au压覆SWNTs,改善SWNTs与电极的接触特性。最后,针对基于SWNTs的柔性微纳传感器进行了力电特性测试。结果表明:在环境温度为(23±5)℃,湿度为65±15%RH,0.1 V工作电压下,压阻因子约为443,精度约为5.16%。上述研究结果在柔性微纳器件的制作方面显示了一定的应用前景,为实现超微型化和高功能密度化的柔性器件铺平道路。     

薄膜型TMA气体传感器的研制

本文报道了采用等离子体ＣＶＤ方法制备Ｆｅ２Ｏ３／ＴｉＯ２薄膜材料，并用浸渍法对表面修饰了Ｉｎ，制成了检测鱼鲜度ＴＭＡ的薄膜气传感器，并具有很好的灵敏度，等。     

基于喷墨打印的可实现敏感材料原位沉积和高温检测的柔性丙酮气体传感器

通过离子交换技术对衬底表面改性,然后喷墨打印掩膜图形,在聚酰亚胺衬底两面分别制备了银叉指电极和加热电阻.通过调节电阻加热器两端的直流偏压,实现25 ℃~280 ℃的控温加热.集成的加热器具有双重功能:纳米ZnO敏感薄膜原位沉积和高温检测.结果表明,该传感器对丙酮气体的灵敏度随温度单调增加(<150 ℃).此外,加热器促进了ZnO敏感薄膜表面丙酮气体分子的解吸,缩短了传感器响应和恢复时间,并减小了初始电阻的漂移.此外,在丙酮检测中,加热器能有效地减少湿度干扰.     

Surface acoustic wave gas sensors based on polyisobutylene and carbon nanotube composites

Surface acoustic wave (SAW) gas sensors based on polyisobutylene (PIB) and composites (PIB and carbon nanotubes) as sensitive layers were investigated for the detection of octane and toluene (volatile organic compounds) and other atmospheric pollutants (H₂, CO, NO₂ and NH₃) at room temperature. In order to study the effect of nanotubes in the response of SAW sensors, several composites based on PIB with different percentages of multiwalled carbon nanotubes (MWNTs) were tested and compared to the response obtained from PIB SAW sensors. Sensors exhibit high responses and selectivity to volatile organic compounds (VOCs) with fast response and recovery times as well as good repeatability and reproducibility. Experimental results show as small percentages of nanotubes improve the response to octane.     

试论家用燃气报警器用气体传感器检定方法

针对家用燃气报警器用的气体传感器的检定方法,提出了不同于报警器检定的、完全针对传感器本身的特性评价的方案,包括检定用模块的规定、符号的规定等.特别是提出了如何使用传感器输出信号的数据,直接评价传感器的报警性能的方法.在此基础上,提出了如何根据报警器检定标准来评价传感器的合格范围,同时提出了对传感器的响应时间、环境试验、...     

Dielectric oil coated single-walled carbon nanotube electrodes for stable, large-strain actuation with dielectric elastomers

Dielectric elastomers have shown remarkably large actuation strain and energy density. A wide range of novel applications have been conceptualized, but commercial devices have not materialized due to the high rates of failure during high-strain actuation. We report that the use of single-walled carbon nanotube (SWNT) layers with thicknesses in the tens of nanometers as the compliant electrodes in combination with dielectric oil can prolong the actuation durability by at least one order of magnitude. Even though the ultrathin SWNT electrodes can undergo localized self-clearing in the event of electrical breakdown, effectively deactivating the fault and enabling self-healing of the device, extended duration actuation at strains larger than 100% in area cannot be achieved. This is due to corona discharge of the highly porous SWNT electrodes that have sharp tips that amplify the electric field. We show that by applying a dielectric oil coating on the SWNT electrodes, the corona discharging is quenched and continuous actuation at larger than 150% strain for longer than 1500 min can be achieved. The combination of self-clearable SWNT electrodes with dielectric oil coating should improve the manufacturing yield and operational reliability of dielectric elastomer artificial muscles and push them closer to commercialization.     

基于随机共振的纳米碳管气体传感器的研究

基于气体电晕放电原理,利用纳米碳管独特的物理结构和尖端发射效应,提出了一种新型的纳米碳管离子型气体传感器.采用阳极氧化铝模板法生长的定向纳米碳管阵列所构成的传感器,纳米碳管和电极是一体的,简化了器件结构和工艺.在外加直流电压激励下,纳米碳管顶部形成很强的非均匀电场,在电压相对低的情况下能很容易地电离气体,根据气体的击穿电压和放电电流来实现对单一气体和确定性混合气体的检测.为了提高检测混合气体的灵敏度,创新地在检测回路中引入随机共振发生装置,有效地提高了混合气体浓度检测的范围.实验中还分析了温度、湿度对传感器的影响,对该传感器的性能也作了评价.实验结果表明该传感器具有选择性好、体积小、响应时间快、灵敏度高、稳定性好,室温操作等优点,而且实现方便,操作简单,有较大的实用价值.     

Development of an ozone gas sensor using single-walled carbon nanotubes

This study deals with the fabrication of an ozone gas sensor using single-walled carbon nanotubes (SWCNTs) as sensing material. The SWCNTs are dispersed by N,N-dimethylformamide (DMF). The CNT-DMF solution was dropped between interdigitated electrodes’ fingers to fabricate ozone gas sensor. For ozone environment, a commercial ozone generator was introduced. To improve sensor response, the deposited carbon nanotubes network was thermally treated at high temperature in a furnace. The sensor exhibits high sensitivity to ozone gas at concentration as low as 50 ppb, and fast response time, which is promising for future commercialization of carbon nanotubes based ozone gas sensor.     

接枝氨基的多壁碳纳米管薄膜传感器的气敏特性研究

制作了接枝氨基的多壁碳纳米管薄膜传感器。研究了其对低体积分数甲醛气体的温度响应特性和膜厚与响应的关系。结果表明：当温度为22℃,薄膜的厚度为8．1μm时,这种薄膜传感器对低体积分数为20×lO-9的甲醛气体的响应可以达到2．9％,此体积分数低于国际卫生组织规定的标准。     

Fast response resistive humidity sensitivity of polyimide/multiwall carbon nanotube composite films

In this study, the fast response resistive humidity sensing properties of polyimide/multiwall carbon nanotube (PI/MWNT) composite films were demonstrated. A composite film with a loading of 3 wt% MWNTs possesses a very linear response nature, a linearity correlation (R²) of 0.99157 and a sensitivity of 0.00146/%RH. The response time was less than 5 s and the resistance changed synchronously with different humidities. The recoverable and repeatable resistive responses affirmed the high efficiency of this film for fast humidity detection. A negative temperature effect was found and proper temperature compensation should be considered in the future applications. Moreover, the humidity sensing properties were presented as a bulk effect owing to water penetration. The stability of the films was proven, which further confirmed that the films could be used as reliable sensor materials. The surfaces of the films were found as an organized structure with nano-size dimples, which is helpful for absorption of water molecules. The proposed sensing mechanisms are related with tunnel effects, doping of MWNTs by water and a barrier effect between MWNTs.