A new approach to the synthesis of titania nano-powders enriched with very high contents of carbon nanotubes by electro-spinning

A new and very simple approach to the synthesis of oxide nanopowders enriched with very high contents of carbon nanotubes (CNTs) is proposed. The procedure consists of three steps: 1) generation of nanofibres over mats of CNTs via the electro-spinning technique; 2) thermo-mechanical treatment of the so-prepared composite to improve interfacial interaction between as-spun fibres and carbonaceous support; 3) calcination in air to obtain the desired oxide from its precursor. Its ease and efficacy are here demonstrated in the case of titania, but the proposed procedure can be extensively used for any other oxide, provided that it can be prepared by ES technique. In this preliminary study, a fixed titanium concentration (0.9wt%) in the solution to be spun is considered, and the influence of titania precursor (titanium butoxide or titanium isopropoxide) and type of polymer (polyvinilpyrrolidone or polyvinilacetate) on morphology and crystalline phase of the oxide nanoparticles is investigated. Viscosity of the precursor/polymer solution is found to chiefly control not only morphology of the oxide, but indirectly also its crystalline phase. CNT load of the hybrids ranges between 38 and 88 wt%.