Preparation and characterization of TiO₂/expanded graphite

Abstract

In order to obtain anatase TiO₂/expanded graphite with high expansion volume, titania gel was introduced to expandable graphite surface by sol-gel process, and then the composite was expanded and calcined at high temperature. The samples were analysed by using scanning electron microscope (SEM), X-ray diffraction(XRD), energy disperse spectroscopy(EDS), and differential scanning calorimetry(DSC). The optimal conditions for preparation are as follows: the molar ratio of tetrabutyl orthotitanate to triethanolamine is 1:0.4, and the calcination and expansion temperature is in the range of 650–750 °C. Under such conditions, the expansion volume of composites could reach 98 mL/g, and the mass loss ratio is less than 5%. The analysis shows that lower temperature and smaller particle size of graphite are helpful to the formation of anatase-type of TiO₂, but larger particle size will lead to lower mass loss ratio, and higher temperature and larger particle size will lead to higher expansion volume.

Keywords

expanded graphite / titanium dioxide / composite / preparation

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