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 fou...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.展开更多
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 ch...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.展开更多
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...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.展开更多
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 si...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.展开更多
文摘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.
基金supported by the National Key Research and Development Program of China(2017YFB0307000)the National Natural Science Foundation of China(51973093,U1533122 and 51773094)+5 种基金the Natural Science Foundation of Tianjin(18JCZDJC36800)the Science Foundation for Distinguished Young Scholars of Tianjin(18JCJQJC46600)the Fundamental Research Funds for the Central Universities(63171219)the State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University(LK1704)the National Special Support Plan for High-level Talents people(C041800902)the Eugene McDermott Graduate Fellows Program。
文摘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.
文摘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.
文摘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.
