碳纳米管网/聚苯胺复合材料的制备及电化学储能性能

分别采用粉末碳纳米管(CNT)和带连接点的碳纳米管网(CNTN)为模板,通过与聚苯胺(PANI)有限域聚合得到了CNT/PANI和CNTN/PANI 2种复合材料.采用透射电子显微镜和扫描电子显微镜对材料的形貌进行了表征,采用氮气吸附-脱附分析研究了材料的孔结构参数,运用双电四探针测试仪对材料的导电性能进行了测试,利用恒流充放电、循环伏安、循环寿命及交流阻抗等电化学测试手段表征了材料的电化学储能性能.结果表明,CNTN/PANI复合材料比CNT/PANI复合材料表现出更好的导电性能和电化学储能性能,其放电比容量可达到143.2 F/g(有机电解液).

Enhanced Field Emission from Printed Carbon Nanotubes by Hard Hairbrush

A method, the morphology of screen printed carbon nanotube pastes is modified using a hard hairbrush, is presented. In this way, the organic matrix material is preferentially removed. Compared to those untreated films, the turn-on electric field of the treated film decreases from 2.2V/μm to 1.6V/μm, while the total emission current of the treated increases from 0.6mA/cm2 to 3mA/cm2, and uniform emission site density image has also been observed.

Experimental investigation of oil particles filtration on carbon nanotubes composite filter

Due to the lipophilicity of carbon nanotubes (CNTs),the carbon nanotubes composite filter for removing oil particles in cooking fumes is synthesized. The composite filter was fabricated by the chemical vapor deposition (CVD) method. The filtration characteristics of the resultant filter and the influence of the parameters were investigated. The results show that the filtration efficiency of the CNT filter during the saturation period is 99.92%, which satisfies the high efficiency particulate air (HEPA) standard. Pressure drop increases linearly before saturation and the pressure drop at the saturation stage is only two times that of the initial stage, which is far less than that of conventional glass fiber filters. The efficiency increases by enhancing filtration velocity. Pressure drops in the composite filter at the equilibrium stage are equal under different aerosol concentrations. The increase in concentration can improve the efficiency of composite filters. Therefore, the CNT filter is suitable for decreasing oil particle pollution due to its lower increase ratio of pressure drop and higher efficiency.

Single-walled carbon nanotube networks for ethanol vapor sensing applications

Networks of pristine high quality single walled carbon nanotubes （SWNTs）, the SWNTs after Ar-plasma treatment （from 2 to 12 rain） and carbon nanobuds （CNBs） have been tested for ethanol vapor sensing. It was found that the pristine high quality SWNTs do not exhibit any ethanol sensitivity, while the introduction of defects in the tubes results in the appearance of the ethanol sensitivity. The CNB network showed ethanol sensitivity without plasma treatment. Both CNB and low defect （after 3 min treatment） SWNT networks exhibit significant drift in the resistance baseline, while heavily plasma-treated （9 min） SWNTs exhibited high ethanol vapor sensitivity without the baseline change. The mechanisms of the ethanol sensitivity and stability after the plasma irradiation are attributed to the formation of sensitive dangling bonds in the SWNTs and formation of defect channels facilitating access of the ethanol vapor to all parts of the bundled nanotubes.

Intrinsic elastic conductors with internal buckled electron pathway for flexible electromagnetic interference shielding and tumor ablation

The elastic conductor is crucial in wearable electronics and soft robotics.The ideal intrinsic elastic bulk conductors show uniform three-dimensional conductive networks and stable resistance during large stretch.A challenge is that the variation of resistance is high under deformation due to disconnection of conductive pathway for bulk elastic conductors.Our strategy is to introduce buckled structure into the conductive network,by self-assembly of a carbon nanotube layer on the interconnecting micropore surface of a prestrained foam,followed by strain relaxation.Both unfolding of buckles and flattening of micropores contributed to the stability of the resistance under deformation(2.0%resistance variation under 70%strain).Microstructural analysis and finite element analysis illustrated different patterns of two-dimensional buckling structures could be obtained due to the imperfections in the conductive layer.Applications as all-directional interconnects,stretchable electromagnetic interference shielding and electrothermal tumor ablation were demonstrated.

Highly uniform carbon nanotube nanomesh network transistors

A new type of single-walled carbon nanotube （SWNT） thin-film transistor （TFT） structure with a nanomesh network channel has been fabricated from a pre- separated semiconducting nanotube solution and simultaneously achieved both high uniformity and a high on/off ratio for application in large-scale integrated circuits. The nanomesh structure is prepared on a high-density SWNT network channel and enables a high on/off ratio while maintaining the excellent uniformity of the electrical properties of the SWNT TFTs. These effects are attributed to the effective elimination of metallic paths across the source/drain electrodes by forming the nanomesh structure in the high-density SWNT network channel. Therefore, our approach can serve as a critical foundation for future nanotube-based thin- film display electronics.

Modeling Frequency- and Temperature-Invariant Dissipative Behaviors of Randomly Entangled Carbon Nanotube Networks under Cyclic Loading

Recent experiments have shown that entangled networks of carbon nanotubes exhibit temperature- and frequency-invariant dissipative behaviors under cyclic loading. We have performed coarse-grained molecular dynamics simulations which show that these intriguing phenomena can be attributed to the unstable attachments/detachments between individual carbon nanotubes induced by van der Waals interactions. We show that this behavior can be described by a triboelastic constitutive model. This study highlights the promise of carbon nanomaterials for energy absorption and dissipation under extreme conditions.