Carbon black (CB), a material consisting of finely divided particles, can be obtained by the partial combustion of heavy petroleum feedstock. The commercial preparation of CB nanoparticles require sophisticated equipment, chemical pre-treatment, and combination of complex separation and purification techniques. CB nanoparticles can also be recovered from scrubbed rubber, but yields are modest and the process is technically complex. Here, we report the development of a simple and inexpensive method for the preparation of CB nanoparticles from waste tires. Under optimal conditions, the yield of recovered CB nanoparticles (∼22 nm) was of approximately 81%; the nanomaterial presents good thermal stability and conductivity, and forms chain-like agglomerates; chemical composition analysis and solubility tests indicates that it is partly oxidized (C, 84.9%; S, 10.21%; O, 4.9%). The product was fully characterized by FTIR, Raman, TGA, BET, SEM and TEM. This preparation method could become a viable alternative to reduce the large amount of waste tires and decreasing their negative environmental impact, producing good quality CB nanoparticles useful for batteries, sensors, electronic devices, catalysis, pigments, concrete, and plastics, among many other applications.

Thin films of nanocomposite of zinc oxide–reduced graphene oxide (ZnO-rGO) deposited on soda-lime glass substrates were prepared using ultrasonic spray pyrolysis (USP) at 460 °C. The preparation process does not use harsh acids and is environmentally friendly. The deposition period of 2, 3.5 and 5 min resulted in compact, uniform samples with thicknesses of 148, 250 and 365 nm, respectively. After performing structural, morphological, optical and electrical characterization of the prepared nanocomposite, an influence of the deposition time on the physical properties of the obtained films was determined. TEM analyses indicate that the ZnO-rGO nanocomposite presents ZnO nanoparticles anchored on graphene sheets, while XRD, X-ray Photoelectron Spectroscopy (XPS) and Raman results show the presence of a ZnO phase in the ZnO-rGO films. HR-SEM studies showed changes of the ZnO-rGO thin films morphology due to the incorporation of graphene into the ZnO films. Here, the particles of ZnO are similar to small grains of rice and graphene films have the appearance of a little “rose”. As the thickness of the film increases with deposition time, it reduces the structure of resistance of the nanocomposite thin films to 135 Ω. In addition, the optical transmission of the thin films in the visible region resulted affected. Here, we report a simple methodology for the preparation of ZnO-rGO nanocomposite thin films.

Silica-coated carbon nanotube has been synthesized through a variety of experimental techniques. In this work, we present results of a route of synthesis for multiwalled carbon nanotubes (MWCNTs)/Silica composites and Silica. This technique involves a reaction of carbon nanotubes dispersed using Gum Arabic with tetraethylorthosilicate (TEOS), Si (OC2H5)4 in solution of ethanol, with NH4OH as catalyst. Characterization of X-ray diffraction, infrared spectroscopy and scanning/transmission electronic microscopy confirmed the MWCNTs/Silica composite synthesis. In this methodology, acids were not used for functionalizing the surface of the carbon nanotubes. We also studied the composite thermal stability. The results of this paper suggest that our methodology can be used to develop less expensive electronic devices such as sensors, biosensors, capacitors, etc. Additionally, our methodology is easy to operate.

We present a simple and versatile technique to fabricate and transfer multi-walled carbon nanotube (MWCNT) membranes to virtually any substrate, including devices and a large variety of materials with different shapes. First, a mesoporous silica (Mobil Composite material MCM-41)/MWCNT composite is deposited by spin coating on SiO₂. Immersion of the wafer in HF solution, releases a floating MWCNT membrane that strongly adheres to any surface that makes contact with it. The process does not require functionalization or surfactants, thus avoiding contamination and additional cleaning steps, and has potential to be extended to allow the fabrication and transfer of membranes of other carbon materials, including other CNT types, fullerenes and graphene.

ZnO/MCM-41 composites consisting of loose particles with an irregular, wrinkled surface and flower-like morphology were obtained by adding MCM-41 to a mixture of zinc nitrate hexahydrate and hexamethylenetetramine under hydrothermal conditions. The physical properties of this composite were determined by scanning electron microscopy (SEM), x-ray powder diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), and photoluminescence spectroscopy (PL). The XRD analysis showed the characteristic diffractogram corresponding to silica overlapped with ZnO peaks, with a reduction in the sharpness and peak intensity, which may be the result of spatial disorder and defects, combined with anisotropic preferential growth. The FTIR spectrum had the characteristic vibrations expected for a silica framework, containing adsorbed water molecules, nitrate ions, and Zn–O bonds. This novel structure may be of particular interest from both fundamental and applied perspectives. It can be advantageous for the adsorption and capture of small molecules. Therefore, it may improve the performance of some previously investigated uses for these ZnO/MCM-41composites, such as photocatalysis and adsorbents for pollutants removal. To the best of our knowledge, this is the first time that wrinkled ZnO/MCM-41 nanocomposite obtained by a low-cost and easy method is reported.