Hybrid materials based nanotubes

Zhang, W.-D., Xu, B. and Jiang, L.-C. (2010) Functional hybrid materials based on carbon nanotubes and metal oxides , /. Mater. Chem, 20,6383-91. 

Felekis, T.A., and Tagmatarchis, N. (2005) Single-walled carbon nanotube-based hybrid materials for managing charge transfer processes. Rev. Adv. Mater. Sci. 10, 272-276. 

Carbon-based sorbents are relatively new materials for the analysis of noble metal samples of different origin [78-84]. The separation and enrichment of palladium from water, fly ash, and road dust samples on oxidized carbon nanotubes (preconcentration factor of 165) [83] palladium from road dust samples on dithiocarbamate-coated fullerene Cso (sorption efficiency of 99.2 %) [78], and rhodium on multiwalled carbon nanotubes modified with polyacrylonitrile (preconcentration factor of 120) [80] are examples of the application of various carbon-based sorbents for extraction of noble metals from environmental samples. Sorption of Au(III) and Pd(ll) on hybrid material of multiwalled carbon nanotubes grafted with polypropylene amine dendrimers prior to their determination in food and environmental samples has recently been described [84]. Recent application of ion-imprinted polymers using various chelate complexes for SPE of noble metals such as Pt [85] and Pd [86] from environmental samples can be mentioned. Hydrophobic noble metal complexes undergo separation by extraction under cloud point extraction systems, for example, extraction of Pt, Pd, and Au with N, A-dihexyl-A -benzylthiourea-Triton X-114 from sea water and dust samples [87]. 

A crucial problem connected to carbon nanotube synthesis on supported catalysts on an industrial scale is the purification step required to remove the support and possibly the catalyst from the final material. To avoid this costly operation, the use of CNT- or CNF-supported catalysts to produce CNTs or CNFs has been investigated. Although most catalytic systems are based on nickel supported on CNFs (see Table 9.4), the use of MWCNTs [305,306] or SWCNTs [307] as supports has also been reported. Nickel, iron [304,308-310], and bimetallic Fe-Mo [305] and Ni-Pd [295] catalysts have been used. Compared to the starting CNTs or CNFs, the hybrid materials produced present higher specific surface area [297,308] or improved field emission characteristics [309]. 

A performant reagentless ECL system for H2O2 detection based on electrop-olymerized luminol on pre-treated screen-printed electrodes was developed [64]. An ECL biosensor based on carboxylic acid-functionaUzed multi-walled carbon nanotubes (CCX)H-F-MWNT) and Au nanoparticles [65] and immobilization in sol-gel hybrid material was fabricated for sensing the efficiency of ethanol. The intensity of ECL increased linearly with ethanol concentration from 2.5 x 10 5.0 X 10 M and detection limit was 1.0 x 10 M [66]. 

Nanobiotechology-based biosensors have been developed with immobilization of biomolecules in miniamrized structures, which may contain hybrid materials for enhancing sensing properties [4, 9-17]. Such methods have also been applied to biosensors based on FEDs [4]. For example, carbon nanotubes (CNTs) have been used in biosensors to achieve better sensitivity and selectivity [18-22]. The key to obtain such enhanced systems is the combination of biomolecules, whose activity may be preserved for long periods of time, and nanomaterials, as CNTs, on the FEDs surface [4]. Deposition of these materials is normally done with the electrostatic layer-by-layer (LbL) technique that allows an easy control of film thickness and possible tuning of molecular architectures to yield tailored sensing units [4, 23-31]. 

However, the largest challenge to the widespread utilization of carbon materials is their poor solubility. Researchers have devoted a great deal of effort to improving their solubility and make them disperse well in typical solvents. Based on the special supramolecular and structural properties of pillar[n]arenes, water-soluble pillararenes are considered to disperse carbon nanotubes and graphene in aqueous solutions. The pillararene-based carbon hybrid materials will be introduced in this section. 

Kosidlo U, et al (2013) Nanocarbon based ionic actuators-a review. Smart Mater Struct 22 104022 Li J, et al (2011) Superfest-response and ultrahigh-power-density electromechanical actuators based on hierarchal carbon nanotube electrodes and chitosan. Nano Lett 11 4636-4641 Lima MD, et al (2012) Electrically, chemically, and photonically powered torsional and tensile actuation of hybrid carbon nanotube yam muscles. Science 338 928-932 Liu Q, et al (2014) Nanostructured carbon materials based electrothermal air pump actuators. Nanoscale 6 6932-6938... 

Neira-Velazquez Maria Guadalupe, Ramos-de Valle Luis Francisco, Hemtodez-Hemandez Ernesto, Zapata-Gonzalez Ivan. Toward greener chemistry methods for preparation of hybrid polymer materials based on carbon nanotubes. e-Polymers, 162,1618-7229,2008. 

Lu, L., et al., Highly stable air working bimorph actuator based on a graphene nanosheet/carbon nanotube hybrid electrode. Advanced Materials, 2012. 24(31) p. 4317-4321. 

Guo, S., S. Dong, and E. Wang, Constructing carbon nanotube/Ptnanoparticle hybrids using an imidazotium-satt-based ionic liquid as a linker. Advanced Materials, 2010. 22(11) p. 1269-1272. 

Nanocarbons are among the most promising materials developed last years. Nanocarbon materials include fullerenes, carbon nanotubes (CNT), carbon nanofibers (CNF), nanodiamond, onions, and various hybrid forms and 3-dimensional structures based on these. Several years ago these materials were available in milligram-scale quantities. Now many of them are produced by tones per year. TMSpetsmash Ltd. research team has developed some new kinds of nanocarbon materials and processes for their production. 

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