Flower-like MoS2 modified with carbon nanospheres (CNS) displays energy-storage capability when used as an aqueous symmetric pseudocapacitor.

Carbon nanofibers (CNFs), cylindrical nanostructures containing graphene, were synthesized directly from South African fly ash (a waste product formed during the combustion of coal). The CNFs (as well as other carbonaceous materials like carbon nanotubes (CNTs)) were produced by the catalytic chemical vapour deposition method (CCVD) in the presence of acetylene gas at temperatures ranging from 400°C to 700°C. The fly ash and its carbonaceous products were characterized by transmission electron microscopy (TEM), thermogravimetric analysis (TGA), laser Raman spectroscopy and Brunauer-Emmett-Teller (BET) surface area measurements. It was observed that as-received fly ash was capable of producing CNFs in high yield by CCVD, starting at a relatively low temperature of 400°C. Laser Raman spectra and TGA thermograms showed that the carbonaceous products which formed were mostly disordered. Small bundles of CNTs and CNFs observed by TEM and energy-dispersive spectroscopy (EDS) showed that the catalyst most likely responsible for CNF formation was iron in the form of cementite; X-ray diffraction (XRD) and Mössbauer spectroscopy confirmed these findings.

The photocatalytic efficiency of TiO2 was improved by compositing it with carbon nanomaterials synthesized using a waste material, fly ash.

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The formation of silver nanoparticles (10-20 nm) inside poly (3-sulfopropyl methacrylate) brushes was studied by using transmission electron microscopy, UV-Vis spectroscopy and X-ray photoelectron spectroscopy (XPS). Initially, the silver forms Ag 2+ 4 clusters that are stabilised by the anionic side groups of the brush. In the presence of a reducing agent, these clusters aggregate into nanoparticles or films. The apparent oxidation state for silver in the different forms was examined using XPS and a chemical state plot. It was seen that the nanoparticles do not display the same chemical shift as the silver film does. The reason for this observation is suggested to be the final and initial state effects. The latter is related to the relatively high amount of under coordinated or charged surface atoms on these particles.