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Electrochemists are racing to develop new organic and inorganic materials for batteries and supercapacitors. As Organic Radical Battery technology approaches, a wide variety of materials are being proposed. However, devising materials with both ionic conductivity and redox storage properties is a strategy to be explored. In this paper, we show a new composite based on mixing carbon nanotubes and redox ionic liquids. The present work's originality is that this composite is realized for the first time and allows a couple of different types of conduction/storage: electronic conduction via carbon nanotubes, ionic conduction via ionic liquids, and redox transport via redox molecules. Flexible composite materials comprised carbon nanotubes and poly(imidazolium) with allyl and redox pendant groups were fabricated and examined. They demonstrated ionic and electrical conductivity and the faradaic response of the redox-polymerized ionic liquid. [ABSTRACT FROM AUTHOR]

Carbon-nanotube (CNT) field-effect transistors (CNFETs) are promising extensions to silicon CMOS. Simulations show that CNFET inverters fabricated with a perfect CNFET technology have 13 times better energy delay product compared with 32-nm silicon CMOS inverters. The following two fundamental challenges prevent the fabrication of CNFET circuits with the aforementioned advantages: 1) misaligned and mispositioned CNTs and 2) metallic CNTs. Misaligned and mispositioned CNTs can cause incorrect functionality. This paper presents a technique for designing arbitrary logic functions using CNFET circuits that are guaranteed to implement correct functions even in the presence of a large number of misaligned and mispositioned CNTs. Experimental demonstration of misaligned and mispositioned CNT-immune logic structures is also presented. [ABSTRACT FROM AUTHOR]

This paper presents a circuit-compatible compact model for the intrinsic channel region of the MOSFET-like single-walled carbon-nanotube field-effect transistors (CNFETs). This model is valid for CNFET with a wide range of chiralities and diameters and for CNFET with either metallic or semiconducting carbon-nanotube (CNT) conducting channel. The modeled nonidealities include the quantum confinement effects on both circumferential and axial directions, the acoustical/optical phonon scattering in the channel region, and the screening effect by the parallel CNTs for CNFET with multiple CNTs. In order to be compatible with both large- (digital) and small-signal (analog) applications, a complete transcapacitance network is implemented to deliver the real-time dynamic response. This model is implemented with an HSPICE. Using this model, we project a 13 times CV/I improvement of the intrinsic CNFET with (19, 0) CNT over the bulk n-type MOSFET at the 32-nm node. The model described in this paper serves as a starting point toward the complete CNFET- device model incorporating the additional device/circuit-level nonidealities and multiple CNTs reported in the paper of Deng and Wong. [ABSTRACT FROM AUTHOR]

This paper presents a complete circuit-compatible compact model for single-walled carbon-nanotube field-effect transistors (CNFETs) as an extension to Part 1 of this two-part paper. For the first time, a universal circuit-compatible CNFET model including the practical device nonidealities is implemented with HSPICE. In addition to the nonidealities included in the companion paper, this paper includes the elastic scattering in the channel region, the resistive source/drain (S/D), the Schottky-barrier resistance, and the parasitic gate capacitances. More than one nanotube per device can be modeled. Compared to silicon technology, the CNFETs show much better device performance based on the intrinsic CV/I gate-delay metric (six times for nFET and 14 times for pFET) than the MOSFET device at the 32-nm node, even with device nonidealities. This large speed improvement is significantly degraded (by a factor of five to eight) by interconnect capacitance in a real circuit environment. We performed circuit-performance comparison with all the standard digital library cells between CMOS random logic and CNFET random logic with HSPICE simulation. Compared to CMOS circuits, the CNFET circuits with one to ten carbon nanotubes per device is about two to ten times faster, the energy consumption per cycle is about seven to two times lower, and the energy-delay product is about 15-20 times lower, considering the realistic layout pattern and the interconnect wiring capacitance. [ABSTRACT FROM AUTHOR]

Carbon nanotube sensors are modeled and their design space analyzed. It is found that semiconducting nanotubes are almost always preferred over metallic nanotubes, intrinsic nanotubes maximize sensor performance, while minimizing static power consumption, and higher biasing points maximize dynamic range, while improving sensitivity. Insights into design of nanoscale sensors for optimal performance are provided, and it is shown that single-molecule analyte detection can be readily achieved with 1 nm diameter nanotubes up to 30 mum in length. [ABSTRACT FROM PUBLISHER]

Nanointerfacial decoration of silver nanoparticles (AgNPs) is an ideal protocol to improve the antibacterial efficiency of diverse nanomaterials, including carbon nanotube (CNT), graphene, and many other intensively studied nanoarchitectures, which provides a tremendous possibility for designing advanced antibacterial biomaterials and biomedical devices. However, the direct exposure of AgNPs will lead to potential mammalian cell apoptosis and death, which significantly limits their biological applications. In this study, we demonstrated a green and one-step approach to achieve robust antibacterial and highly biocompatible AgNP-CNT composites. AgNPs were produced via mussel-inspired "one-step" in situ reduction and coating process and were anchored onto the surface of a CNT. Simultaneously, protective polymer layers were formed to shield the AgNPs to improve their biocompatibility. Because of the bactericidal efficiency of AgNPs, the composites showed robust antibacterial efficiency in terms of both inhibition of bacterial cell growth and bacterial killing activity. Moreover, owing to the shielding effects of the polymer coatings, the nanocomposites exhibited much improved compatibility with human umbilical vein endothelial cells compared with bare AgNP-CNTs. Furthermore, the nanocomposites exhibited good stability in psychological solutions. With integrated excellent antibacterial activity, cell compatibility, and long-term stability, it is believed that the synthesized AgNP-CNT composites will be of promising potential in antibacterial applications. Meanwhile, the proposed strategies can also be applied to fabricate many other kinds of AgNP-based composites because of the versatile functionality of catecholic polymers. [ABSTRACT FROM AUTHOR]

Combining the advantages of the fibrous nanostructure of carbon nanotubes (CNTs) and the bioactivities of heparin/heparin-mimicking polyanions, functional nanofibrous heparin or heparin-mimicking multilayers were constructed on PVDF membrane with highly promoted endothelialization and antithrombogenic activities. Oxidized CNT (oCNT) was first functionalized with water-soluble chitosan (polycation), then enwrapped with heparin or a typical sulfonated heparin-mimicking polymers (poly(sodium 4-styrenesulfonate-co-sodium methacrylate)) to construct the multilayers. Then, the surface-deposited multilayers were constructed via electrostatic layer-by-layer assembly of the functionalized oCNTs. The scanning electron microscope and atom force microscope images confirmed that the coated multilayers exhibited nanofibrous and porous structure. The live/dead cell staining and cell viability assay results indicated that the coated nanofibrous multilayers had excellent compatibility with endothelial cells. The cell morphology observation further confirmed the promotion ability of surface endothelialization due to the coated heparin/heparin-mimicking multilayers. Further systematical evaluation on blood compatibility revealed that the surface heparin/heparin-mimicking multilayer-coated membranes also had significantly improved blood compatibility including restrained platelet adhesion and activation, prolonged blood clotting times, and inhibited activation of coagulation and complement factors. In summary, the proposed nanofibrous multilayers integrated endothelialization and antithrombogenic properties; meanwhile, the heparin-mimicking coating validated comparable performances as heparin coating. Herein, it is expected that the surface coating of nanofibrous multilayers, especially the facilely constructed heparin-mimicking coating, may have great application potential in biomedical fields. [ABSTRACT FROM AUTHOR]