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This work investigated the effects of iodine on copper/functionalized carbon nanotubes (Cu/f-CNT) that were used in the coating of 1350 Aluminum Alloy wires, using the process of electrophoretic exposure with a solution of copper sulfate and iodine, under an electrical current of 1.2 A and a voltage of 10 V. The Al@Cu/f-CNT was characterized by Scanning Electron Microscopy in Secondary Electron mode, X-ray Diffraction and Raman spectroscopy, in addition to electrical measurements, at room temperature and under heating, via kelvin bridge. The results showed an increase of approximately 18% in the electrical conductivity of the IACS compared to the standard aluminum conductor, due to the iodine doping of the outer walls of the f-CNT, causing an expansion between the layers, and reflecting the increase in the conduction channels. This method of electrodeposition of Cu/f-CNT on the surface of metallic wires shows promise for the production of nanostructured cables with high ampacity, lightness and high performance, for application in power transmission lines.

The development of electronic gadgets has become of great relevance for the detection of fraud in beverages such as wine, due to the addition of adulterants that bring risks to human health as well as economic impacts. Thus, the present study aims to apply a buckypaper (BP) based on functionalized multiwalled carbon nanotubes (MWCNTs)/cellulose fibers as a sensor for the analysis of Port wine intentionally adulterated with 5 vol.% and 10 vol.% distilled water and ethyl alcohol. The morphology of BP characterized by scanning electron microscopy indicates the formation of agglomerates of random MWCNTs dispersed on the surface and between the fibers of the cellulosic paper. The analysis of the response of the film through the normalized relative resistance change showed a higher response of 0.75 ± 0.16 for adulteration with 10 vol.% of water and a mean response time of 10.0 ± 3.60 s and recovery of approximately 17.2 min for adulteration with 5 vol.% alcohol. Principal component analysis (PCA) was used in data processing to evaluate the ability of BP to recognize and discriminate analytes and adulterating agents, allowing the investigation of its potential application as a low-cost and easy-to-handle multisensor.

Carbon nanotubes (CNTs) exhibit excellent electrical and thermal properties that have been used in several device assemblies, such as electrode sheets made from an aggregate of CNTs, also called as buckypaper (BP). Despite that, the properties of single CNTs are reduced when randomly assembled to form a BP. In this way, this study investigated the thermoelectric effect of a BP electrode assembled on a copper electrode with an active area of 4.0 cm2. The micrographs were obtained by scanning electron microscopy and show morphology agglomerated of multiwalled CNTs, which permeated into the filter paper, forming a thickness of 67.33 μm. Moreover, indoor/outdoor tests were performed approaching the BP electrode from a heat source. Thus, the electrical responses in function of temperature variation show maximum thermovoltages of 9.0 mV and 40.73 mV from indoor and outdoor tests, respectively. Finally, an average Seebeck coefficient for the BP/copper electrodes array of 35.34 ± 6.0 mV/K was estimated from 298 to 304 K. These findings suggest that this assembly will be easily applied in thermoelectric device concepts.

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