Interconnected Carbon Nanotube Networks Research Articles

Improving Mechanical, Electrical and Thermal Properties of Fluororubber by Constructing Interconnected Carbon Nanotube Networks with Chemical Bonds and F-H Polar Interactions.

To improve the properties of fluororubber (FKM), aminated carbon nanotubes (CNTs-NH2) and acidified carbon nanotubes (CNTs-COOH) were introduced to modulate the interfacial interactions in FKM composites. The effects of chemical binding and F-H polar interactions between CNTs-NH2, CNTs-COOH, and FKM on the mechanical, electrical, thermal, and wear properties of the FKM composites were systematically investigated. Compared to the pristine FKM, the tensile strength, modulus at 100% strain, hardness, thermal conductivity, carbon residue rate, and electrical conductivity of CNTs-NH2/CNTs-COOH/FKM were increased by 112.2%, 587.5%, 44.2%, 37.0%, 293.5%, and nine orders of magnitude, respectively. In addition, the wear volume of CNTs-NH2/CNTs-COOH/FKM was reduced by 29.9%. This method provides a new and effective way to develop and design high-performance fluororubber composites.

A Wavy-Structured Highly Stretchable Thermoelectric Generator with Stable Energy Output and Self-Rescuing Capability

A Wavy-Structured Highly Stretchable Thermoelectric Generator with Stable Energy Output and Self-Rescuing Capability

Facile co-deposition of the carbon nanotube@MnO2 heterostructure for high-performance flexible supercapacitors

Herein, a facile co-deposition method is developed to synthesize carbon nanotube (CNT)@MnO2 heterostructures grown on carbon fibre paper (CFP) and flexible carbon fibre cloth (CFC) (denoted as CNT@MnO2/CFP and CNT@MnO2/CFC, respectively). A three-dimensional (3D) interconnected CNT network of highly conductive, ultrathin CNT@MnO2 heterostructure nanosheets with a nanoporous structure and with epitaxial growth of MnO2 on the CNTs achieves excellent capacitance performance for flexible MnO2-based supercapacitor materials. The CNT@MnO2/CFP fabricated in an electrolyte with CNT content of 0.5 g L−1 (0.5-CNT@MnO2/CFP) obtains mass, area and volume specific capacitance values of 393.0 F g−1, 585.0 mF cm−2 and 29.3 F cm−3, respectively, at a charge-discharge rate of 0.25 A g−1. A flexible asymmetric supercapacitor device was successfully assembled which possesses a high energy density of 27.8 Wh kg−1 at a high power density of 250 W kg−1 (0.75 mA cm−2) and a high capacitance retention of 84% after 10,000 performs at a charge-discharge rate of 15 mA cm−2 (5 A g−1). Our work confirmed that this structure can effectively improving the utilization and specific capacitance of MnO2, and the simplicity of the fabrication and the environmentally friendly characteristics of the deposition liquid make this approach suitable for practical production.

Electronic tongue and cyclic voltammetric sensors based on carbon nanotube/polylactic composites fabricated by fused deposition modelling 3D printing.

In this work, 3D printed electrodes fabricated by blending Polylactic acid (PLA) with carbon nanotube (CNT), CNT/copper (Cu), CNT/zinc oxide (ZnO) composites were applied as cyclic voltammetric sensors for electronic tongue analysis. Porous rectangular rod-shape electrodes were fabricated by fused-deposition-modelling 3D printing of the CNT-based composites produced by a solution blending method. The physical and chemical properties of 3D printed electrodes were characterized by scanning electron microscopy, X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, four-point-probe electrical tests and thermoelectric measurements. The characterization results confirmed uniform distributions of CNTs, Cu particles and ZnO nanorods in the composites and high electrical conductivity of interconnected CNT networks. The additions of Cu and ZnO nanostructures slightly modified the electrical conductivity but significantly changed thermoelectric properties of the material. Cyclic voltammetric (CV) data demonstrated satisfactory stability of the composite materials under corrosive CV conditions. In addition, Cu and ZnO additives provided distinct electrochemical behaviors towards K4Fe(CN)6, H2O2 and nicotinamide adenine dinucleotide. Principal component analysis of CV features could effectively distinguish the three chemicals with various concentrations, illustrating the possibility to apply 3D printed CNT/PLA-based electrodes for electronic tongue applications.

Continuous nitrogen-doped carbon nanotube matrix for boosting oxygen electrocatalysis in rechargeable Zn-air batteries

Interconnected Carbon Nanotube Network: Continuous nanocarbon matrix composed of abundant interconnected nitrogen-doped carbon nanotubes demonstrates efficient and stable oxygen electrocatalysis for long-life rechargeable Zn-air batteries. Developing robust oxygen electrocatalyst with high-performance is very significant for practical rechargeable Zn-air battery. We report herein the preparation of three-dimensional continuous nanocarbon network composed of interconnected nitrogen-doped carbon nanotubes and its application as oxygen electrocatalysis in rechargeable Zn-air battery. Except the excellent electrochemical bifunctionality, this carbon nanotube matrix also delivers an impressive battery performance. Specifically, an open-circuit voltage of 1.50 V as well as a high power density of 220 mW cm −2 with remarkable cycling stability for 1600 h is achieved in the rechargeable Zn-air battery. The study not only provides an efficient bifunctional oxygen electrocatalyst but more importantly may pave significant concepts in designing robust electrode for long-life rechargeable Zn-air battery and other energy technologies.

Constructing 2D SnS@C nanosheets anchored on interconnected carbon nanotube networks as advanced anode materials for lithium ion and sodium ion batteries

The huge volume change and sulfur dissolution during the repeated discharge/charge process is believed to be the main cause of fast capacity decay and poor rate capability of SnS for LIBs and SIBs. Here, SnS@C nanosheets anchored on interconnected CNT networks are designed and prepared as anode materials for LIBs and SIBs is reported. Thanks to the synergistic function between SnS nanosheets, CNT and carbon coating layers, the obtained SnS/CNT@C composite exhibits outstanding cycling/rate performance for LIBs and SIBs. Meanwhile, high specific capacity of 494.9 mAh g−1 is maintained after 400 loops at 1.0 A g−1, excellent rate performance (431 mAh g−1 at 5.0 A g−1) is achieved for LIBs. Furthermore, SnS/CNT@C composite also demonstrated a high reversible capacity (582.6 mAh g−1 at 0.2 A g−1) and long-term cycling performance (243.3 mAh g−1 is obtained after 400 loops at 0.5 A g−1) for SIBs.

In Situ Confined Bimetallic Metal-Organic Framework Derived Nanostructure within 3D Interconnected Bamboo-like Carbon Nanotube Networks for Boosting Electromagnetic Wave Absorbing Performances.

Metal-organic framework (MOFs) derived magnetic nanoparticles/porous carbon (M/C) composites featuring efficient interfacial engineering and spatially continuous three-dimensional (3D) networks are desirable electromagnetic wave (EMW) absorbing materials due to multiple transmission path and well impedance matching. However, it is challenging to construct such 3D interconnected carbon networks from a single MOF precursor. Herein, FeNi3 and N embedded 3D carbon networks comprising bamboo-like carbon nanotubes connected carbon nanorods (FeNi@CNT/CNRs) were prepared via one-step pyrolyzing of the composite of melamine and FeNi-MIL-88B. Attributed to the synergistic contributions of 3D interconnected carbon nanotube networks and MOFs derived M/C for multiple transmission path, impedance matching, and dielectric loss (especially for multiple polarization and micro-current), the FeNi@CNT/CNRs nanoarchitectures have demonstrated superior EMW absorbing performance. In particular, the optimized FeNi@CNT/CNR-0.9 has exhibited strong absorption (-47.0 dB, 2.3 mm in thickness) and broadband effective absorption (4.5 GHz, 1.6 mm in thickness). This attractive strategy holds promise as a general approach to fabricate the carbon hybrid network constituted of MOFs derived nanopolyhedron and CNTs for the target application.

A tin disulfide nanosheet wrapped with interconnected carbon nanotube networks for application of lithium sulfur batteries

The shuttle effect of lithium polysulfides (LiPSs) seriously affects the cycle and rate capability performances of lithium sulfur batteries (LSBs) and restricts their commercial application. In order to suppress availably the shuttle effect of LiPSs, herein a holistic design strategy for using tin disulfide nanosheet wrapped with interconnected carbon nanotube networks (SnS2@CNT) as the sulfur host and separator of LSBs is put forward. Based on the advantages of physical internment and chemistry absorption for LiPSs as well fast electron/lithium ion transport of SnS2@CNT, the LSBs with SnS2@CNT/S-SnS2@CNT release a high initial discharge specific capacity of 1375 mAh g−1 at 0.1C. After 800 cycles a high reversible specific capacity of 555 mAh g−1 can still be obtained even at a high current density of 2C. Besides, the LSBs with the high sulfur loading of 4.8 mg cm−2 can exhibit a reversible areal capacity of 4.5 mAh cm−2 after 50 cycles. Therefore, the design strategy provides a beneficial exploration for the commercialization of high-performance LSBs.

Mono-dispersed ultra-long single-walled carbon nanotubes as enabling components in transparent and electrically conductive thin films

We report on a simple and practical method for creation of transparent and electrically conductive films by using ultra-long single-walled carbon nanotubes (SWCNTs) as the functioning elements. The ultra-long SWCNTs were ultimately dispersed into tubular levels for dispersion (denoted as mono-dispersion) in aqueous solutions by using glycocholate mixed with cholate as the dispersant. The resulting colloids were cast uniformly over the surface of flexible polyethylene terephthalate film through a wire-bar coating process. After washing by diluted nitric acid, the dispersants have been largely eliminated while the carbon nanotubes have been firmly retained on the surface of the film. These carbon nanotubes were finally transferred and permanently immobilized onto the surface of another piece of film with cellulose as the binder. Serial film samples each having different densities of the carbon nanotubes on the surface were prepared for studying the conductive mechanism. Film samples having densities around 30-tubes per μm2 were found to be capable of creating continuously interconnected carbon nanotube networks with a 92% transparency and a 286Ω/sq resistivity through the formation of approximately 160 tube-to-tube junctions per μm2. These highly conductive and transparent films transfer electrons by the carbon nanotube networks with a slightly deformed tube-to-tube junction feature.

Temperature-dependent electrical and photo-sensing properties of horizontally-oriented carbon nanotube networks synthesized by sandwich-growth microwave plasma chemical vapor deposition

The electrical and photo-sensing properties of horizontally-oriented interconnected carbon nanotube networks (CNT-NWs) prepared by means of a microwave plasma chemical vapor deposition sandwich-growth process are investigated. The temperature-dependent dark and illuminated current–voltage and transfer characteristics of CNT-NW-assisted devices are measured. Results show that the current–voltage characteristics of the devices exhibit nonlinear behavior, and the current can be further modulated by a gate voltage, revealing p-type semiconducting behavior with a device mobility of ~14.5cm2/V·s and an on-off current ratio of ~103. Moreover, when the CNT-NW-assisted devices are irradiated with 1.25–25μm infrared (IR) from 300 to 11K, the photo currents increase approximately 1.1- to 2.7-fold compared to the dark currents at ±2V bias voltage. Such results demonstrate that the presented CNT-NWs have high potential for IR photo-sensor applications.

Structure Characterization and Electrochemical Characteristics of Carbon Nanotube- Spinel Li4Ti5O12Nanoparticles

ABSTRACTCarbon nanotube-spinel lithium titanate (CNT-Li4Ti5O12) nanoparticles have been synthesized by hydrothermal reaction and higher-temperature calcinations with LiOH·H2O and TiO2precursors in the presence of carbon nanotubes sources. The CNT-Li4Ti5O12nanoparticles have been characterized by X-ray diffraction (XRD), high angle annular dark field (HAADF) images, and selected area electron diffraction (SAED). The particles exhibited a spinel cubic crystal phase and homogenous size distribution, with sizes around 50-70 nm. HAADF imaging confirmed that carbon content exists on the surface of the CNT-Li4Ti5O12nanoparticles with graphitic carbon coating of 3-5 nm thickness under 800oC in the Ar gas. The graphitic carbon phase was further confirmed with Raman spectroscopy analysis on powder samples. Electrochemical characteristics were evaluated with galvanostatic discharge/charge tests, which showed that the initial discharge capacity is 172 mA·h/g at 0.1C. The nanoscale carbon layers uniformly coated the particles, and the interconnected carbon nanotube network is responsible for the improved charge rate capability and conductivity.

Solubilization of carbon nanotubes by cellulose xanthate toward the fabrication of enhanced amperometric detectors

Negatively charged cellulose xanthate was employed as a solubilizing agent of carbon nanotubes to prepare a highly stable aqueous suspension. The obtained mixture was subsequently allowed to coagulate on disc electrodes in sulfuric acid solution to prepare carbon nanotube–cellulose composite modified electrodes as sensitive amperometric detectors of capillary electrophoresis. The structure and morphology of the prepared carbon nanotube–cellulose composite were investigated by fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy techniques. The results indicated that carbon nanotubes were well dispersed and embedded throughout the regenerated cellulose to form an interconnected carbon nanotube network on the base electrodes. The performance of the unique carbon nanotube-based detectors was demonstrated by separating and detecting four phenolic compounds in combination with capillary electrophoresis. The novel carbon nanotube-based detectors offered significantly lower operating potentials, substantially enhanced signal-to-noise characteristics, and lower expense of operation.

Carbon‐Nanotube–Alginate Composite Modified Electrode Fabricated by In Situ Gelation for Capillary Electrophoresis

This report describes the development and the application of a novel carbon-nanotube (CNT)-alginate composite modified electrode as a sensitive amperometric detector for capillary electrophoresis (CE). The composite electrode was fabricated on the basis of in situ gelation of a mixture of CNTs and sodium alginate on the surface of a carbon disc electrode in aqueous calcium chloride solution. SEM, energy-dispersive spectroscopy, XRD, and FTIR spectroscopy offered insights into the nature of the novel composite. The results indicated that the CNTs were well dispersed and embedded throughout the alginate matrix to form an interconnected carbon-nanotube network on the base electrode. The performance of this unique CNT-based detector has been demonstrated, in conjunction with CE, by separating and detecting five caffeic acid derivatives. The new CNT-based CE detector offered significantly lower operating potentials, substantially enhanced signal-to-noise characteristics, and a lower expense of operation. The simplicity and significant performance exhibited by the CNT-alginate composite modified electrode also indicate great promise for the use of this electrode in microchip CE, flowing-injection analysis, and other microfluidic analysis systems.