Showing papers on "Carbon nanotube published in 2018"
TL;DR: A critical look at the status of composites for developing high-strength, low-density, high-conductivity materials with nanotubes or graphene is presented, pointing out the challenges and opportunities that exist in the field.
Abstract: Composite materials with carbon nanotube and graphene additives have long been considered as exciting prospects among nanotechnology applications. However, after nearly two decades of work in the area, questions remain about the practical impact of nanotube and graphene composites. This uncertainty stems from factors that include poor load transfer, interfacial engineering, dispersion, and viscosity-related issues that lead to processing challenges in such nanocomposites. Moreover, there has been little effort to identify selection rules for the use of nanotubes or graphene in composite matrices for specific applications. This review is a critical look at the status of composites for developing high-strength, low-density, high-conductivity materials with nanotubes or graphene. An outlook of the different approaches that can lead to practically useful nanotube and graphene composites is presented, pointing out the challenges and opportunities that exist in the field.
580 citations
TL;DR: This critical revies assesses the recent development of various functionalized carbon nanotubes and graphene that are used to remove heavy metals from contaminated water, including the preparation and characterization methods of functionalizedhene and graphene, their applications for heavy metal adsorption, effects of water chemistry on the Adsorption capacity, and decontamination mechanism.
569 citations
TL;DR: A novel and effective approach is developed for synthesizing ultrafine Co nanoparticles encapsulated in nitrogen-doped carbon nanotubes grafted onto both sides of reduced graphene oxide (rGO) by direct annealing of GO-wrapped core-shell bimetallic zeolite imidazolate frameworks, which may open a new avenue toward the development of nonprecious high-performance HER catalysts.
Abstract: The rational design of an efficient and inexpensive electrocatalyst based on earth-abundant 3d transition metals (TMs) for the hydrogen evolution reaction still remains a significant challenge in the renewable energy area. Herein, a novel and effective approach is developed for synthesizing ultrafine Co nanoparticles encapsulated in nitrogen-doped carbon nanotubes (N-CNTs) grafted onto both sides of reduced graphene oxide (rGO) (Co@N-CNTs@rGO) by direct annealing of GO-wrapped core-shell bimetallic zeolite imidazolate frameworks. Benefiting from the uniform distribution of Co nanoparticles, the in-situ-formed highly graphitic N-CNTs@rGO, the large surface area, and the abundant porosity, the as-fabricated Co@N-CNTs@rGO composites exhibit excellent electrocatalytic hydrogen evolution reaction (HER) activity. As demonstrated in electrochemical measurements, the composites can achieve 10 mA cm-2 at low overpotential with only 108 and 87 mV in 1 m KOH and 0.5 m H2 SO4 , respectively, much better than most of the reported Co-based electrocatalysts over a wide pH range. More importantly, the synthetic strategy is versatile and can be extended to prepare other binary or even ternary TMs@N-CNTs@rGO (e.g., Co-Fe@N-CNTs@rGO and Co-Ni-Cu@N-CNTs@rGO). The strategy developed here may open a new avenue toward the development of nonprecious high-performance HER catalysts.
494 citations
TL;DR: In this article, a review of nitrogen-doped carbon materials is presented, focusing on their preparation and applications, in the order of graphene, carbon nanotube and fibers, porous carbons and carbon blacks.
482 citations
TL;DR: NiSA-N-CNTs show an excellent selectivity and activity for the electrochemical reduction of CO2 to CO, achieving a turnover frequency (TOF) of 11.7 s-1 at -0.55 V (vs reversible hydrogen electrode (RHE)), two orders of magnitude higher than Ni nanoparticles supported on CNTs.
Abstract: Single-atom catalysts (SACs) are the smallest entities for catalytic reactions with projected high atomic efficiency, superior activity, and selectivity; however, practical applications of SACs suffer from a very low metal loading of 1-2 wt%. Here, a class of SACs based on atomically dispersed transition metals on nitrogen-doped carbon nanotubes (MSA-N-CNTs, where M = Ni, Co, NiCo, CoFe, and NiPt) is synthesized with an extraordinarily high metal loading, e.g., 20 wt% in the case of NiSA-N-CNTs, using a new multistep pyrolysis process. Among these materials, NiSA-N-CNTs show an excellent selectivity and activity for the electrochemical reduction of CO2 to CO, achieving a turnover frequency (TOF) of 11.7 s-1 at -0.55 V (vs reversible hydrogen electrode (RHE)), two orders of magnitude higher than Ni nanoparticles supported on CNTs.
477 citations
TL;DR: In this paper, the EMI shielding effectiveness of flexible polymer composites comprising of metals and various forms of carbon nanofillers such as carbon black, carbon nano-frillers, carbon nanotubes, graphite, graphene, graphene oxide, graphene nanosheets and graphene nanoribbons has been deeply reviewed.
Abstract: The rapid proliferation and elevated usage of electronic devices have led to a meteoritic rise in electronic pollutions such as electronic noise, electromagnetic interference (EMI) and radiofrequency interference (RFI) which leads to improper functioning of electronic devices. Metals and their alloys can serve as the best EMI shielding materials but their heavy weight, high cost and low corrosion resistance have limited their applications in EMI shielding. The emergence of flexible polymer composites have substituted the metal and metal alloy based EMI shielding materials due to their unique features such as light weight, excellent corrosion resistance, superior electrical, dielectric, thermal, mechanical and magnetic properties that are highly useful for suppressing the electromagnetic noises. In this review article, the EMI shielding effectiveness of flexible polymer composites comprising of metals and various forms of carbon nanofillers such as carbon black, carbon nanofibers, carbon nanotubes, graphite, graphene, graphene oxide, graphene nanosheets, graphene nanoribbons and graphene nanoplatelets have been deeply reviewed.
466 citations
TL;DR: Progress made toward understanding the fundamental thermoelectric properties of SWCNTs, nanotube-based composites, and thermoeLECTric devices prepared from these materials is reviewed in detail, illuminates the tremendous potential that carbon-nanotubes-based materials and composites have for producing high-performance next-generation devices for thermoelectedric-energy harvesting.
Abstract: Conversion of waste heat to voltage has the potential to significantly reduce the carbon footprint of a number of critical energy sectors, such as the transportation and electricity-generation sectors, and manufacturing processes. Thermal energy is also an abundant low-flux source that can be harnessed to power portable/wearable electronic devices and critical components in remote off-grid locations. As such, a number of different inorganic and organic materials are being explored for their potential in thermoelectric-energy-harvesting devices. Carbon-based thermoelectric materials are particularly attractive due to their use of nontoxic, abundant source-materials, their amenability to high-throughput solution-phase fabrication routes, and the high specific energy (i.e., W g-1 ) enabled by their low mass. Single-walled carbon nanotubes (SWCNTs) represent a unique 1D carbon allotrope with structural, electrical, and thermal properties that enable efficient thermoelectric-energy conversion. Here, the progress made toward understanding the fundamental thermoelectric properties of SWCNTs, nanotube-based composites, and thermoelectric devices prepared from these materials is reviewed in detail. This progress illuminates the tremendous potential that carbon-nanotube-based materials and composites have for producing high-performance next-generation devices for thermoelectric-energy harvesting.
433 citations
TL;DR: In this paper, the enhancement of thermal conductivity by the introduction of highly thermally conductive metallic and carbon-based nanoparticles, metallic foams, expanded graphite and encapsulation of PCM is discussed.
427 citations
TL;DR: In this paper, spin spray layer-by-layer (SSLbL) is used to rapidly assemble Ti3C2Tx MXene-carbon nanotube (CNT) composite films and their potential for EMI shielding is demonstrated.
Abstract: Lightweight, flexible, and electrically conductive thin films with high electromagnetic interference (EMI) shielding effectiveness are highly desirable for next-generation portable and wearable electronic devices. Here, spin spray layer-by-layer (SSLbL) to rapidly assemble Ti3C2Tx MXene-carbon nanotube (CNT) composite films is shown and their potential for EMI shielding is demonstrated. The SSLbL technique allows strategic combinations of nanostructured materials and polymers providing a rich platform for developing hierarchical architectures with desirable cross-functionalities including controllable transparency, thickness, and conductivity, as well as high stability and flexibility. These semi-transparent LbL MXene-CNT composite films show high conductivities up to 130 S cm−1 and high specific shielding effectiveness up to 58 187 dB cm2 g−1, which is attributed to both the excellent electrical conductivity of the conductive fillers (i.e., MXene and CNT) and the enhanced absorption with the LbL architecture of the films. Remarkably, these values are among the highest reported values for flexible and semi-transparent composite thin films. This work could offer new solutions for next-generation EMI shielding challenges.
375 citations
TL;DR: A "freeze-spinning" technique is used to realize continuous and large-scale fabrication of fibers with aligned porous structure, mimicking polar bear hairs, which is difficult to achieve by other methods.
Abstract: Animals living in the extremely cold environment, such as polar bears, have shown amazing capability to keep warm, benefiting from their hollow hairs. Mimicking such a strategy in synthetic fibers would stimulate smart textiles for efficient personal thermal management, which plays an important role in preventing heat loss and improving efficiency in house warming energy consumption. Here, a "freeze-spinning" technique is used to realize continuous and large-scale fabrication of fibers with aligned porous structure, mimicking polar bear hairs, which is difficult to achieve by other methods. A textile woven with such biomimetic fibers shows an excellent thermal insulation property as well as good breathability and wearability. In addition to passively insulating heat loss, the textile can also function as a wearable heater, when doped with electroheating materials such as carbon nanotubes, to induce fast thermal response and uniform electroheating while maintaining its soft and porous nature for comfortable wearing.
364 citations
TL;DR: A 3D catalyst, composed of nanoparticles of CoFe alloy embedded in N-doped carbon nanotubes tangled with reduced graphene oxide, was developed, which presents appreciable ORR/OER activity when applied in a Zn-air battery.
Abstract: Low-cost, efficient bifunctional electrocatalysts are needed to mediate the oxygen reduction and oxygen evolution reactions (ORR/OER) in Zn-air batteries. Such catalysts should offer binary active sites and an ability to transfer oxygen-based species and electrons. A 3D catalyst, composed of nanoparticles of CoFe alloy embedded in N-doped carbon nanotubes tangled with reduced graphene oxide, was developed, which presents appreciable ORR/OER activity when applied in a Zn-air battery. A high open-circuit voltage of 1.43 V, a stable discharge voltage of 1.22 V, a high energy efficiency of 60.1 %, and excellent stability after 1 600 cycles at 10 mA cm-2 are demonstrated. An all-solid-state battery had an outstanding lifetime and high cell efficiency even upon bending. In situ X-ray absorption spectroscopy revealed that OOH* and O* intermediates induce variations in the Fe-Fe and Co-Co bond lengths, respectively, suggesting that Fe and Co species are crucial to the ORR/OER processes.
Wright-Patterson Air Force Base1, Vanderbilt University2, University of Manchester3, University of Cambridge4, Lawrence Livermore National Laboratory5, University of Southern California6, Massachusetts Institute of Technology7, Kansas State University8, Yale University9, Rice University10, Texas A&M University11, Aix-Marseille University12, National Institute of Advanced Industrial Science and Technology13, Waseda University14, National Research Council15, Aalto University16, University of Wisconsin-Madison17, Georgia Institute of Technology18, Tsinghua University19, Brookhaven National Laboratory20, University of Pennsylvania21, Peking University22, Pennsylvania State University23, Oak Ridge National Laboratory24, University of Tokyo25
TL;DR: While the primary focus of this review is on the science framework of SWCNT growth, connections to mechanisms underlying the synthesis of other 1D and 2D materials such as boron nitride nanotubes and graphene are drawn.
Abstract: Advances in the synthesis and scalable manufacturing of single-walled carbon nanotubes (SWCNTs) remain critical to realizing many important commercial applications. Here we review recent breakthroughs in the synthesis of SWCNTs and highlight key ongoing research areas and challenges. A few key applications that capitalize on the properties of SWCNTs are also reviewed with respect to the recent synthesis breakthroughs and ways in which synthesis science can enable advances in these applications. While the primary focus of this review is on the science framework of SWCNT growth, we draw connections to mechanisms underlying the synthesis of other 1D and 2D materials such as boron nitride nanotubes and graphene.
TL;DR: Based on a single-electrode mode triboelectric nanogenerator and electrode pattern design, a washable E-textile exhibits highly sensitive touch/gesture sensing performance and has potential applications for human-machine interfacing.
Abstract: Multifunctional electronic textiles (E-textiles) with embedded electric circuits hold great application prospects for future wearable electronics. However, most E-textiles still have critical challenges, including air permeability, satisfactory washability, and mass fabrication. In this work, we fabricate a washable E-textile that addresses all of the concerns and shows its application as a self-powered triboelectric gesture textile for intelligent human–machine interfacing. Utilizing conductive carbon nanotubes (CNTs) and screen-printing technology, this kind of E-textile embraces high conductivity (0.2 kΩ/sq), high air permeability (88.2 mm/s), and can be manufactured on common fabric at large scales. Due to the advantage of the interaction between the CNTs and the fabrics, the electrode shows excellent stability under harsh mechanical deformation and even after being washed. Moreover, based on a single-electrode mode triboelectric nanogenerator and electrode pattern design, our E-textile exhibits highl...
TL;DR: Here, the recent advances in flexible ASSSCs are summarized, from design strategies to fabrication techniques for nanocarbon electrodes and devices, and great achievements have been obtained.
Abstract: Because of the rapid development of flexible electronics, it is important to develop high-performance flexible energy-storage devices, such as supercapacitors and metal-ion batteries. Compared with metal-ion batteries, supercapacitors exhibit higher power density, longer cycling life, and excellent safety, and they can be easily fabricated into all-solid-state devices by using polymer gel electrolytes. All-solid-state supercapacitors (ASSSCs) have the advantages of being lightweight and flexible, thus showing great potential to be used as power sources for flexible portable electronics. Because of their high specific surface area and excellent electrical and mechanical properties, nanocarbon materials (such as carbon nanotubes, graphene, carbon nanofibers, and so on) have been widely used as efficient electrode materials for flexible ASSSCs, and great achievements have been obtained. Here, the recent advances in flexible ASSSCs are summarized, from design strategies to fabrication techniques for nanocarbon electrodes and devices. Current challenges and future perspectives are also discussed.
TL;DR: In this paper, a series of nitrogen-doped carbon nanotubes (NCNTFs) with distinguishable nitrogen content and graphitization degree have been successfully prepared through in situ transformation of ZIF-67 under N2/H2 atmosphere at different pyrolysis temperature.
TL;DR: A lithiophilic-lithiophobic gradient interfacial ZnO/CNT layer is introduced, which facilitates the formation of a stable solid electrolyte interphase, and suppresses the growth of lithium dendrite.
Abstract: The long-standing issue of lithium dendrite growth during repeated deposition or dissolution processes hinders the practical use of lithium-metal anodes for high-energy density batteries. Here, we demonstrate a promising lithiophilic–lithiophobic gradient interfacial layer strategy in which the bottom lithiophilic zinc oxide/carbon nanotube sublayer tightly anchors the whole layer onto the lithium foil, facilitating the formation of a stable solid electrolyte interphase, and prevents the formation of an intermediate mossy lithium corrosion layer. Together with the top lithiophobic carbon nanotube sublayer, this gradient interfacial layer can effectively suppress dendrite growth and ensure ultralong-term stable lithium stripping/plating. This strategy is further demonstrated to provide substantially improved cycle performance in copper current collector, 10 cm2 pouch cell and lithium–sulfur batteries, which, coupled with a simple fabrication process and wide applicability in various materials for lithium-metal protection, makes the lithiophilic–lithiophobic gradient interfacial layer a favored strategy for next-generation lithium-metal batteries.
TL;DR: In this paper, a multistep templating method has been exploited for the rational design and synthesis of SnS 2 nanosheets confined in carbon nanotubes (SnS 2 @CNTs) to demonstrate the universality of this method.
TL;DR: In this article, a review on the synthesis method of graphene and application of graphene oxide-based nanomaterials in the term of heavy metal removal from wastewater is presented, where the advantages, drawbacks, comparison of the data efficiencies, and research requirements are further highlighted, elaborated and discussed detailly.
TL;DR: It is discovered that the inner dense CNT serves as a robust skeleton, and collectively, the outer loose-CNT is beneficial for K-ion accommodation; meanwhile the hyperporous sponge facilitates reaction kinetics and offers stable surface capacitive behavior.
Abstract: Recently, commercial graphite and other carbon-based materials have shown promising properties as the anode for potassium-ion batteries. A fundamental problem related to those carbon electrodes, significant volume expansion, and structural instability/collapsing caused by cyclic K-ion intercalation, remains unsolved and severely limits further development and applications of K-ion batteries. Here, a multiwalled hierarchical carbon nanotube (HCNT) is reported to address the issue, and a reversible specific capacity of 232 mAh g-1 , excellent rate capability, and cycling stability for 500 cycles are achieved. The key structure of the HCNTs consists of an inner CNT with dense-stacked graphitic walls and a loose-stacked outer CNT with more disordered walls, and individual HCNTs are further interconnected into a hyperporous bulk sponge with huge macropore volume, high conductivity, and tunable modulus. It is discovered that the inner dense-CNT serves as a robust skeleton, and collectively, the outer loose-CNT is beneficial for K-ion accommodation; meanwhile the hyperporous sponge facilitates reaction kinetics and offers stable surface capacitive behavior. The hierarchical carbon nanotube structure has great potential in developing high-performance and stable-structure electrodes for next generation K and other metal-ion batteries.
TL;DR: In this paper, multi-walled carbon nanotubes (MWCNT)-based, graphene-based, and MWCNT/graphene-based composite phase change materials (PCM) were prepared and experimentally studied to improve the performance of lithium-ion power battery thermal management system.
TL;DR: An effective method for bonding carbon nanotubes (CNTs) onto carbon fibers (CFs) surface via layer-by-layer (LBL) grafting method is reported in this article.
TL;DR: This work suggests the application of the stretchable and skin-attachable electrochemical sensor for detecting glucose and pH in sweat from running while being attached onto the skin as a high-performance healthcare wearable device.
Abstract: As part of increased efforts to develop wearable healthcare devices for monitoring and managing physiological and metabolic information, stretchable electrochemical sweat sensors have been investigated. In this study, we report on the fabrication of a stretchable and skin-attachable electrochemical sensor for detecting glucose and pH in sweat. A patterned stretchable electrode was fabricated via layer-by-layer deposition of carbon nanotubes (CNTs) on top of patterned Au nanosheets (AuNS) prepared by filtration onto stretchable substrate. For the detection of glucose and pH, CoWO4/CNT and polyaniline/CNT nanocomposites were coated onto the CNT–AuNS electrodes, respectively. A reference electrode was prepared via chlorination of silver nanowires. Encapsulation of the stretchable sensor with sticky silbione led to a skin-attachable sweat sensor. Our sensor showed high performance with sensitivities of 10.89 μA mM–1 cm–2 and 71.44 mV pH–1 for glucose and pH, respectively, with mechanical stability up to 30% s...
TL;DR: This review paper summarizes the synthesis of various carbon nanomaterials via the chemical vapor deposition (CVD) method, including fullerenes, carbon nanotubes (CNTs), carbon nanofibers (CNFs), graphene, carbide-derived carbon (CDC), carbon nano-onion (CNO) and MXenes.
Abstract: Carbon nanomaterials have been extensively used in many applications owing to their unique thermal, electrical and mechanical properties. One of the prime challenges is the production of these nanomaterials on a large scale. This review paper summarizes the synthesis of various carbon nanomaterials via the chemical vapor deposition (CVD) method. These carbon nanomaterials include fullerenes, carbon nanotubes (CNTs), carbon nanofibers (CNFs), graphene, carbide-derived carbon (CDC), carbon nano-onion (CNO) and MXenes. Furthermore, current challenges in the synthesis and application of these nanomaterials are highlighted with suggested areas for future research.
TL;DR: In this article, the recent advances in photothermal actuators based on various carbon allotropes, including graphite, carbon nanotubes, amorphous carbon, graphene and its derivatives, are reviewed.
Abstract: Actuators that can convert environmental stimuli into mechanical work are widely used in intelligent systems, robots, and micromechanics. To produce robust and sensitive actuators of different scales, efforts are devoted to developing effective actuating schemes and functional materials for actuator design. Carbon-based nanomaterials have emerged as preferred candidates for different actuating systems because of their low cost, ease of processing, mechanical strength, and excellent physical/chemical properties. Especially, due to their excellent photothermal activity, which includes both optical absorption and thermal conductivities, carbon-based materials have shown great potential for use in photothermal actuators. Herein, the recent advances in photothermal actuators based on various carbon allotropes, including graphite, carbon nanotubes, amorphous carbon, graphene and its derivatives, are reviewed. Different photothermal actuating schemes, including photothermal effect–induced expansion, desorption, phase change, surface tension gradient creation, and actuation under magnetic levitation, are summarized, and the light-to-heat and heat-towork conversion mechanisms are discussed. Carbon-based photothermal actuators that feature high light-to-work conversion efficiency, mechanical robustness, and noncontact manipulation hold great promise for future autonomous systems.
TL;DR: In this article, nano-TiNb2O7 and its carbon nanotube (CNT) nanocomposites were prepared by direct hydrolysis of TiNb10O29-type crystal structure with O2− vacancies and lower-valence cations, leading to improved Li+-ion diffusion coefficient and increased electronic conductivity.
TL;DR: The fabricated CNTBs, consisting of a large number of components with parallel alignment, defect-free structures, continuous lengths and uniform initial strains, exhibit a tensile strength of 80 GPa, which is far higher than that of any other strong fibre.
Abstract: Carbon nanotubes (CNTs) are one of the strongest known materials. When assembled into fibres, however, their strength becomes impaired by defects, impurities, random orientations and discontinuous lengths. Fabricating CNT fibres with strength reaching that of a single CNT has been an enduring challenge. Here, we demonstrate the fabrication of CNT bundles (CNTBs) that are centimetres long with tensile strength over 80 GPa using ultralong defect-free CNTs. The tensile strength of CNTBs is controlled by the Daniels effect owing to the non-uniformity of the initial strains in the components. We propose a synchronous tightening and relaxing strategy to release these non-uniform initial strains. The fabricated CNTBs, consisting of a large number of components with parallel alignment, defect-free structures, continuous lengths and uniform initial strains, exhibit a tensile strength of 80 GPa (corresponding to an engineering tensile strength of 43 GPa), which is far higher than that of any other strong fibre.
TL;DR: Wang et al. as discussed by the authors used a simple and facile solution mixing-casting method to fabricate a highly stretchable strain sensor based on composites mixing polydimethylsiloxane (PDMS) with hybrid carbon nanotubes (CNTs) and carbon black (CB) conductive nanofillers.
15 Jan 2018
TL;DR: Recent developments in carbon‐based sunlight absorbers in solar‐driven steam generation systems are reviewed, including graphene, graphite, carbon nanotubes, other carbon materials, and carbon‐ based composite materials, highlighting important contributions worldwide that promise low‐cost, efficient, robust, reusable, chemically stable, and excellent broadband solar absorption.
Abstract: Carbon-based sunlight absorbers in solar-driven steam generation have recently attracted much attention due to the possibility of huge applications of low-cost steam for medical sterilization or sanitization, seawater desalination, chemical distillation, and water purification. In this minireview, recent developments in carbon-based sunlight absorbers in solar-driven steam generation systems are reviewed, including graphene, graphite, carbon nanotubes, other carbon materials, and carbon-based composite materials, highlighting important contributions worldwide that promise low-cost, efficient, robust, reusable, chemically stable, and excellent broadband solar absorption. Furthermore, the crucial challenges associated with employing carbon materials in this field are emphasized.
TL;DR: 2D CCP-HATN hybridized with carbon nanotubes shows a high capacity, high utilization of its redox-active sites and superb cycling stability and rate capability as an organic cathode material for lithium-ion batteries.
Abstract: A two-dimensional (2D) sp2 -carbon-linked conjugated polymer framework (2D CCP-HATN) has a nitrogen-doped skeleton, a periodical dual-pore structure and high chemical stability. The polymer backbone consists of hexaazatrinaphthalene (HATN) and cyanovinylene units linked entirely by carbon-carbon double bonds. Profiting from the shape-persistent framework of 2D CCP-HATN integrated with the electrochemical redox-active HATN and the robust sp2 carbon-carbon linkage, 2D CCP-HATN hybridized with carbon nanotubes shows a high capacity of 116 mA h g-1 , with high utilization of its redox-active sites and superb cycling stability (91 % after 1000 cycles) and rate capability (82 %, 1.0 A g-1 vs. 0.1 A g-1 ) as an organic cathode material for lithium-ion batteries.
TL;DR: A self-supporting and flexible activated carbon/carbon nanotube/reduced graphene oxide (AC/CNT/RGO) film has been rationally designed for constructing high-performance supercapacitor as mentioned in this paper.