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1.
Concha Bosch‐Navarro Eugenio Coronado Carlos Martí‐Gastaldo Benito Rodríguez‐González Luis M. Liz‐Marzán 《Advanced functional materials》2012,22(5):979-988
Two different routes that enable the electrostatic grafting of cationic single‐molecule magnets (SMMs) onto the surface of chemically modified anionic multi‐walled carbon nanotubes (MWNTs) are described. The chemical nature and physical properties of the resulting hybrids are discussed on the basis of a complete battery of experimental techniques. The data show that the chemical nature of the SMM unit remains intact, while its magnetic response is significantly affected by the grafting process, which is likely due to surface effects. 相似文献
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纳米分子电子器件是未来电子器件发展的重要方向。对几种典型的纳米分子电子器件,如纳米分子开关、纳米分子整流器、纳米分子晶体管、纳米分子电磁器件和纳米分子电光器件的工作原理、应用前景等方面进行了介绍,同时分析了各自的优势与问题所在。这一领域所遇到的主要挑战问题在于器件的可靠性与生产的高成本。目前纳米分子电子器件的发展趋势和研究重点是通过对器件原理的深入研究以及制备方法的不断探索,找到提高器件可靠性的方法以及解决降低成本和适应市场化的问题。 相似文献
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High spin polarization materials or spin filters are key components in spintronics, a niche subfield of electronics where carrier spins play a functional role. Carrier transmission through these materials is “spin selective,” that is, these materials are able to discriminate between “up” and “down” spins. Common spin filters include transition metal ferromagnets and their alloys, with typical spin selectivity (or, polarization) of ≈50% or less. Here carrier transport is considered in an archetypical one‐dimensional molecular hybrid in which a single wall carbon nanotube (SWCNT) is wrapped around by single stranded deoxyribonucleic acid (ssDNA). By magnetoresistance measurements it is shown that this system can act as a spin filter with maximum spin polarization approaching ≈74% at low temperatures, significantly larger than transition metals under comparable conditions. Inversion asymmetric helicoidal potential of the charged ssDNA backbone induces a Rashba spin‐orbit interaction in the SWCNT channel and polarizes carrier spins. The results are consistent with recent theoretical work that predicted spin dependent conductance in ssDNA‐SWCNT hybrid. Ability to generate highly spin polarized carriers using molecular functionalization can lead to magnet‐less and contact‐less spintronic devices in the future. This can eliminate the conductivity mismatch problem and open new directions for research in organic spintronics. 相似文献
4.
David Brunel Costin Anghel Do‐Yoon Kim Saïd Tahir Stéphane Lenfant Arianna Filoramo Takis Kontos Dominique Vuillaume Vincent Jourdain Vincent Derycke 《Advanced functional materials》2013,23(45):5631-5637
Nano‐objects would be of great interest for the development of new types of electronic circuits if one could combine their nanometer scale with original functionalities beyond the conventional transistor action. However, the associated circuit architectures will have to handle the increasing variability and defect rate intrinsic to the nanoscale. In this context, there is a very fast growing interest for memory devices, and in particular resistive memory devices, used as building blocks in reconfigurable circuits tolerant to defects and variability. It was recently shown that optically gated carbon nanotube field effect transistors (OG‐CNTFETs) based on large assemblies of nanotubes covered by an organic photoconductive thin film can be operated as programmable resistors and thus used as artificial synapses in circuits with function‐learning capabilities. Here, the potential of such approach is evaluated in terms of scalability by integrating and addressing several individually programmable resistances on a single carbon nanotube. In addition, the charge storage mechanism can be controlled at a length scale smaller than the device length allowing to also program the direction in which the current flows. It thus demonstrates that a single nanotube section can combine all‐in‐one the properties of an analog resistive memory and of a rectifying diode with tunable polarity. 相似文献
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Abdulaziz S. R. Bati LePing Yu Munkhbayar Batmunkh Joseph G. Shapter 《Advanced functional materials》2019,29(30)
Single‐walled carbon nanotubes (SWCNTs) exhibit outstanding properties that make them appealing in a wide range of applications. However, their properties are variable depending on the tube helicity (chirality), which has been a challenge for a long time and needs to be effectively controlled. In recent years, tremendous efforts have been made to control the electrical type/chirality of nanotubes through both direct controlled synthesis and postsynthesis separation methods. Driven by these breakthroughs, the applications of separated families of SWCNTs in various fields have emerged as a new topic of research. In this Review, an overview of recent advances in the use of highly purified and well‐separated SWCNTs in a comprehensive range of applications is presented including photovoltaics, transistors, batteries, sensors, light emitters, biological/medical fields, and others. Finally, important future directions for the utilization of separated SWCNTs in these fields are provided. 相似文献
7.
Wytse Talsma Aprizal Akbar Sengrian Jorge Mario Salazar‐Rios Herman Duim Mustapha Abdu‐Aguye Stefan Jung Sybille Allard Ullrich Scherf Maria Antonietta Loi 《Advanced Electronic Materials》2019,5(8)
In the past years, high‐quality semiconducting single‐walled carbon nanotube (s‐SWCNT) inks obtained by conjugated polymer wrapping using toluene as solvent have been used for the fabrication of high‐performance field‐effect transistors. Charge‐carrier mobilities up to 50 cm2 V−1 s−1 and on/off ratios above 108 have been reported for devices based on networks of s‐SWCNT. However, devices fabricated from inks that are only a few weeks old generally show a marked decrease in performance, indicating the limited shelf life of toluene‐based inks. The use of o‐xylene as applicator solvent to obtain high quality and very stable s‐SWCNT inks is reported. The charge carrier mobility of field‐effect transistors fabricated with this new ink show a twofold increase in magnitude compared to devices prepared from a toluene solution. More importantly, the device‐to‐device performance shows improved reproducibility, which is ascribed to the higher degree of homogeneity of the s‐SWCNT network deposited from o‐xylene with respect to the one from toluene. Finally, the o‐xylene inks maintain their initial properties for longer than one year. This very long shelf life is an important pre‐condition for the industrial use of s‐SWCNT inks. 相似文献
8.
Widianta Gomulya Vladimir Derenskyi Erika Kozma Mariacecilia Pasini Maria Antonietta Loi 《Advanced functional materials》2015,25(36):5858-5864
Polymer wrapped single‐walled carbon nanotubes (SWNTs) have been demonstrated to be a very efficient technique to obtain high purity semiconducting SWNT solutions. However, the extraction yield of this technique is low compared to other techniques. Poly‐alkyl‐thiophenes have been reported to show higher extraction yield compare to polyfluorene derivatives. Here, the affinity for semiconducting SWNTs of two polymers with a backbone containing didodecylthiophene units interspersed with N atoms is reported. It is demonstrated that one of the polymers, namely, poly(2,5‐dimethylidynenitrilo‐3,4‐didodecylthienylene) (PAMDD), has very high semiconducting SWNT extraction yield compared to the poly(3,4‐didodecylthienylene)azine (PAZDD). The dissimilar wrapping efficiency of these two polymers for semiconducting SWNTs is attributed to the interplay between the affinity for the nitrogen atoms of the highly polarizable walls of SWNTs and the mechanical flexibility of the polymer backbones. Photoluminescence (PL) measurements demonstrate the presence of metallic tubes and SWNT bundles in the sample selected with PAZDD and higher purity of SWNT‐PAMDD samples. The high purity of the semiconducting SWNTs selected by PAMDD is further demonstrated by the high performance of the solution‐processed field‐effect transistors (FETs) fabricated using a blade coating technique, which exhibit hole mobilities up to 33.3 cm2 V?1 s?1 with on/off ratios of 106. 相似文献
9.
Jon K. S. Baldwin Nicolai F. Hartmann Stephen K. Doorn Han Htoon 《Advanced functional materials》2015,25(39):6157-6164
A novel procedure for effective fabrication of photostable oxygen‐doped single‐walled carbon nanotubes (SWCNTs) in solid‐state matrices has been developed. SWCNTs drop‐cast on various types of substrates are coated with oxide dielectric thin films by electron‐beam evaporation. Single tube photoluminescence spectroscopy studies performed at room and cryogenic temperatures reveal that such thin film‐coated tubes exhibit characteristic spectral features of oxygen‐doped SWCNTs, indicating the oxide thin film coating process leads to oxygen doping of the tubes. It is also found that the doping efficiency can be effectively controlled by the thin film deposition time and by the types of surfactants wrapping the SWCNTs. Moreover, aside from being the doping agent, the oxide thin film also serves as a passivation layer protecting the SWCNTs from the external environment. Comparing the thin film coated SWCNTs with oxygen‐doped tubes prepared via ozonolysis, the former exhibit significantly higher photostability and photoluminescence on‐time. Therefore, this one‐step deposition/oxygen‐doping procedure provides a possible route toward scalable, versatile incorporation of highly photostable oxygen‐doped SWCNTs in novel optical and optoelectronic devices. 相似文献
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Antonio Setaro Pascal Bluemmel Chandan Maity Stefan Hecht Stephanie Reich 《Advanced functional materials》2012,22(11):2425-2431
Single‐walled carbon nanotubes (SWCNTs) are functionalized with a spiropyran derivative, which is attached non‐covalently to the SWCNT's sidewall via a pyrene anchor group. Using this non‐covalent functionalization strategy, individual SWCNTs can be stabilized in solution without the need for additional surfactants. Bright luminescence confirms the presence of individual tubes in the thus‐prepared samples. In these samples, the majority of pyrene‐spiropyran molecules are attached to the walls of the SWCNTs. Upon complex formation with the SWCNT, the switching moiety retains its ability to switch, i.e., to undergo reversible transformations between the closed spiropyran and the opened merocyanine form, and is stable over many cycles of operation. 相似文献
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Nan Zhang Weiya Zhou Zhiqiang Niu Qiang Zhang Xiao Zhang Feng Yang Qingxia Fan Wenbin Zhou Zhuojian Xiao Xiaogang Gu Huiliang Chen Kewei Li Shiqi Xiao Yanchun Wang Huaping Liu Sishen Xie 《Advanced functional materials》2016,26(45):8178-8184
Recent development in epidermal and bionic electronics systems has promoted the increasing demand for supercapcacitors with micrometer‐thickness and good compatibility. Here, a highly flexible free‐standing epidermal supercapacitor (SC‐E) with merely 1 μm thickness and high performance is developed. Single‐walled carbon nanotube/poly(3,4‐ethylenedioxythiophene) hybrid films with unique inner‐connected reticulation are adopted as electrodes for ultrathin structure and high electric conductivity. Then, based on two substrates with different surface energies, a stepwise lift‐off method is presented to peel off the ultrathin integrated supercapacitor from the substrates nondestructively. As a result of the high conductive hybrid electrodes and the thin electrolyte layer, the as‐designed supercapacitors (based on the total mass of two electrodes) achieve a good capacitance of 56 F g?1 and a superhigh power density of 332 kW kg?1, which manifest superior performance in contrast to the other devices fabricated by traditional electrodes. Meanwhile, the ultrashort response time of 11.5 ms enables the epidermal supercapacitor (SC‐E) work for high‐power units. More importantly, the free‐standing structure and outstanding flexibility (105 times bending) endow the SC‐E with excellent compatibility to be integrated and work in the next generation of smart and epidermal systems. 相似文献
13.
Supercapacitors: Epidermal Supercapacitor with High Performance (Adv. Funct. Mater. 45/2016) 
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下载免费PDF全文 Pingshan Luan Nan Zhang Weiya Zhou Zhiqiang Niu Qiang Zhang Le Cai Xiao Zhang Feng Yang Qingxia Fan Wenbin Zhou Zhuojian Xiao Xiaogang Gu Huiliang Chen Kewei Li Shiqi Xiao Yanchun Wang Huaping Liu Sishen Xie 《Advanced functional materials》2016,26(45):8149-8149
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Divya K. Chakravarthi Valery N. Khabashesku Ranji Vaidyanathan Jeanette Blaine Shridhar Yarlagadda David Roseman Qiang Zeng Enrique V. Barrera 《Advanced functional materials》2011,21(13):2527-2533
Multifunctional carbon fiber composites are imperative for next‐generation lightweight aircraft structures. However, lightning‐strike protection is a feature that is lacking in many modern carbon fiber high‐temperature polymer systems, due to their high electrical resistivity. This work presents a study on processing, materials optimization, and property development of high‐temperature bismaleimide (BMI)–carbon fiber composites filled with nickel‐coated single‐walled carbon nanotubes (Ni‐SWNTs) based on three key factors: i) dispersion of Ni‐SWNTs, ii) their surface coverage on the carbon plies and, iii) the composite surface resistivity. Atomic force microscopy analysis revealed that coating purified SWNTs with nickel enabled improved dispersion which resulted in uniform surface coverage on the carbon plies. The electrical resistivity of the baseline composite system was reduced by ten orders of magnitude by the addition of 4 wt% Ni‐SWNTs (calculated with respect to the weight of a single carbon ply). Ni‐SWNT–filled composites showed a reduced amount of damage to simulated lightning strike compared to their unfilled counterparts, as indicated by the minimal carbon fiber pull‐out. 相似文献
15.
K. H. An W. S. Kim Y. S. Park J.‐M. Moon D. J. Bae S. C. Lim Y. S. Lee Y. H. Lee 《Advanced functional materials》2001,11(5):387-392
We have investigated the key factors determining the performance of supercapacitors constructed using single‐walled carbon nanotube (SWNT) electrodes. Several parameters, such as composition of the binder, annealing temperature, type of current collector, charging time, and discharging current density have been optimized for the best performance of the supercapacitor with respect to energy density and power density. We find a maximum specific capacitance of 180 F/g and a measured power density of 20 kW/kg at energy densities in the range from 7 to 6.5 Wh/kg at 0.9 V in a solution of 7.5 N KOH (the currently available supercapacitors have energy densities in the range 6–7 Wh/kg and power density in the range 0.2–5 kW/kg at 2.3 V in non‐aqueous solvents). 相似文献
16.
A microwave‐induced controlled method for the purification of single‐walled carbon nanotubes (SWCNTs) by removing residual metal catalysts and carbonaceous impurities is reported. Compared to conventional strong acid treatment, this one‐step method uses dilute acids and complexing agents and reduces the reaction times to the order of minutes. Furthermore, the SWCNTs retain their chemical and physical properties and are not functionalized. Electron microscopy, Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and atomic absorption (AA) spectrometry studies were used to characterize the purified SWCNTs. 相似文献
17.
Changwoo Doe Sung‐Min Choi Steven R. Kline Hyung‐Sik Jang Tae‐Hwan Kim 《Advanced functional materials》2008,18(18):2685-2691
A new dispersant for stabilization of single wall carbon nanotubes (SWNTs) in water that simultaneously utilizes three different dispersion or stabilization mechanisms: surfactant adsorption, polymeric wrapping, and Coulomb repulsive interaction, has been demonstrated. The new dispersant, a charged rod‐like nanoparticle (cROD), is a cylindrical micelle wrapped by negatively charged polymers which is fabricated by the aqueous free radical polymerization of a polymerizable cationic surfactant, cetyltrimethylammonium 4‐vinylbenzoate (CTVB), in the presence of sodium 4‐styrenesulfonate (NaSS). The surface charge density of the cRODs is controlled by varying the concentration of NaSS. Dispersions of SWNTs are obtained by sonicating a mixture of SWNTs and cROD in water, followed by ultra‐centrifugation and decanting. While the cRODs with neutral or low surface change densities (0 and 5 mol % NaSS) result in very low dispersion power and poor stability, the cRODs with high surface charge densities (15, 25, and 40 mol % NaSS) produce excellent dispersions with SWNT concentration as high as 437 mg L?1 and long term stability. The sharp van Hove transition peaks of the cROD assisted SWNT dispersions indicate the presence of individually isolated SWNTs. Atomic force microscopy and small angle neutron scattering analysis show that the dominant encapsulation structure of the cROD assisted SWNTs is surfactant assisted polymeric wrapping. SWNTs dispersed by the cRODs can be fully dried and easily re‐dispersed in water, providing enhanced processibility of SWNTs. 相似文献
18.
Vincent Tiing Tiong Ngoc Duy Pham Teng Wang Tianxiang Zhu Xinluo Zhao Yaohong Zhang Qing Shen John Bell Linhua Hu Songyuan Dai Hongxia Wang 《Advanced functional materials》2018,28(10)
Organic–inorganic lead halide perovskites have shown great future for application in solar cells owing to their exceptional optical and electronic properties. To achieve high‐performance perovskite solar cells, a perovskite light absorbing layer with large grains is desirable in order to minimize grain boundaries and recombination during the operation of the device. Herein, a simple yet efficient approach is developed to synthesize perovskite films consisting of monolithic‐like grains with micrometer size through in situ deposition of octadecylamine functionalized single‐walled carbon nanotubes (ODA‐SWCNTs) onto the surface of the perovskite layer. The ODA‐SWCNTs form a capping layer that controls the evaporation rate of organic solvents in the perovskite film during the postthermal treatment. This favorable morphology in turn dramatically enhances the short‐circuit current density of the perovskite solar cells and almost completely eliminates the hysteresis. A maximum power conversion efficiency of 16.1% is achieved with an ODA‐SWCNT incorporated planar solar cell using (FA0.83MA0.17)0.95Cs0.05Pb(I0.83Br0.17)3 as light absorber. Furthermore, the perovskite solar cells with ODA‐SWCNT demonstrate extraordinary stability with performance retention of 80% after 45 d stability testing under high humidity (60–90%) environment. This work opens up a new avenue for morphology manipulation of perovskite films and enhances the device stability using carbon material. 相似文献
19.
Linda Chio Rebecca L. Pinals Aishwarya Murali Natalie S. Goh Markita P. Landry 《Advanced functional materials》2020,30(17)
Optical nanoscale technologies often implement covalent or noncovalent strategies for the modification of nanoparticles, whereby both functionalizations are leveraged for multimodal applications but can affect the intrinsic fluorescence of nanoparticles. Specifically, single‐walled carbon nanotubes (SWCNTs) can enable real‐time imaging and cellular delivery; however, the introduction of covalent SWCNT sidewall functionalizations often attenuates SWCNT fluorescence. Recent advances in SWCNT covalent functionalization chemistries preserve the SWCNT's pristine graphitic lattice and intrinsic fluorescence, and here, such covalently functionalized SWCNTs maintain intrinsic fluorescence‐based molecular recognition of neurotransmitter and protein analytes. The covalently modified SWCNT nanosensor preserves its fluorescence response towards its analyte for certain nanosensors, presumably dependent on the intermolecular interactions between SWCNTs or the steric hindrance introduced by the covalent functionalization that hinders noncovalent interactions with the SWCNT surface. These SWCNT nanosensors are further functionalized via their covalent handles with a targeting ligand, biotin, to self‐assemble on passivated microscopy slides, and these dual‐functionalized SWCNT materials are explored for future use in multiplexed sensing and imaging applications. 相似文献
20.
Jianhui Chen Lu Wan Han Li Jun Yan Jikui Ma Biao Sun Feng Li Benjamin S. Flavel 《Advanced functional materials》2020,30(38)
Traditional silicon solar cells extract holes and achieve interface passivation with the use of a boron dopant and dielectric thin films such as silicon oxide or hydrogenated amorphous silicon. Without these two key components, few technologies have realized power conversion efficiencies above 20%. Here, a carbon nanotube ink is spin coated directly onto a silicon wafer to serve simultaneously as a hole extraction layer, but also to passivate interfacial defects. This enables a low‐cost fabrication process that is absent of vacuum equipment and high‐temperatures. Power conversion efficiencies of 21.4% on an device area of 4.8 cm2 and 20% on an industrial size (245.71 cm2) wafer are obtained. Additionally, the high quality of this passivated carrier selective contact affords a fill factor of 82%, which is a record for silicon solar cells with dopant‐free contacts. The combination of low‐dimensional materials with an organic passivation is a new strategy to high performance photovoltaics. 相似文献