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There is a growing demand for nanoparticles coated with graphene due their promise in various applications such as batteries and supercapacitors, sorbents, and biomedical applications. A good example is Si where its combination with carbon is considered important for electronics and energy applications, such as lithium ion batteries, polymer based composites and even bio-medical applications. In this study, we aim to develop a very simple chemical vapor deposition approach to form graphitized Si nanoparticles in which ethanol serves as the C feedstock. This differs from other CVD approaches which tend to use a gaseous hydrocarbon (e.g. CH 4 ) as the carbon feedstock. The use of ethanol in which Ar is simply bubbled through liquid ethanol leads to a simpler and cheaper approach. Moreover, in conventional CVD, often an oxidant (e.g. CO 2 ) is added to aid graphitization and minimize the formation of SiC at the Si surface. Ethanol provides a source of O which serves as an inbuilt oxidizer to aid graphitization and limit the formation of SiC. The simple synthesis approach allows one to tailor the number of graphene layers coating the Si nanoparticles through the three main synthesis parameters of ethanol supply, temperature and reaction time. Moreover, using ethanol as the precursor, lower graphitization temperatures than for methane can be used.

Three-dimensional (3D) nanostructured graphene can be used as a replacement or enrichment material. This review presents the types of 3D graphene developed thus far, for example, nanoshells, encapsulates, graphene foams, aerogels and hydrogels, their properties and the methods by which to obtain them, such as chemical vapour deposition, the hydrothermal method or by sugar-blowing production. The review also covers areas in which 3D graphene foam has been exploited for application such as energy, electronic, biomedical and environmental protection as well as the latest developments.

Carbon nanotubes (CNTs) have recently emerged as one of the most promising structures for thermoelectrics (TE). As compared with typical thermoelectric materials, CNTs can be made from almost any carbon-bearing precursor, and so at present thousands of tonnes of them are produced annually at every corner of the world. In this work, we synthesized multi-walled CNTs (MWCNTs) and doped them with heteroatoms of nitrogen, boron or phosphorus to tune their thermoelectric performance. The research showed that MWCNTs doped with nitrogen or boron had improved thermoelectric properties by up to three orders of magnitude as compared with the undoped material. Because of the different modes of charge transport by electrons and holes, respectively, they could be used to construct functional thermoelectric modules.