Disordered carbon materials with high porosity were prepared through the pyrolysis of TiO2/poly(furfuryl alcohol) composites, obtained by the sol-gel method. The composites were prepared starting from titanium tetra-isopropoxide (TTIP) and furfuryl alcohol (FA) as precursors. Two different synthetic procedures for our composites were carried out, based on the addition of furfuryl alcohol (FA) before or after the TiO_2 nanoparticles formation. Also, different TTIP/FA ratio was tested. The hybrid materials obtained by both synthetic routes were pyrolyzed, under argon flow, at 900 deg C producing novel TiO_2/carbon composites. All samples were characterized by XRD, FT-IR, DR-FTIR, Raman spectroscopy and TEM. Results indicated the effective FA polymerization on TiO_2 (anatase) nanoparticles, and polymer conversion to disordered carbon after the pyrolysis, simultaneously with TiO_2 anatase-rutile phase transition. The resulting TiO_2/carbon composites were treated with HF solution aiming the oxide dissolution, yielding an extremely porous carbon material as insoluble fraction. The morphology of these porous carbon materials is strongly dependent on the synthetic route adopted for the composite precursor, varying from carbon foam to highly ordered hollow microspheres.
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