In this work, we present the growth and optical characterization of carbon nanotube/TiO2 anatase nanocomposites. The composites are obtained by doping a bulk of anatase nanometric grains with different weight percentages of carbon nanotube (from 0.1% to 50%). We observe that only for tube concentrations between 0.1% and 2%, the growth process shows the formation of a matrix where carbon nanotubes are uniformed and dispersed in a bulk of TiO2 grains. Moreover, the X-ray photoelectron spectroscopy and surface morphology analysis (conducted from AFM images) indicated that the CNT absorption is a simple physisorption without chemical bonds formations between tube and dioxide. Finally, absorption in all the visible range has the increase of about 60% at very low concentration (2%) of carbon nanotubes.
 M. Hemissi and H. Amardjia-Adnani, “Optical and Structural Properties of Titanium Oxide Thin Fils Prepared by Sol-Gel Method,” Digest Journal of Nanomaterials and Biostructures, Vol. 2, No. 4, 2007, pp. 299-305.
 R. Zallem and M. P. Moret, “The Optical Absorption Edge of Brookite TiO2,” Solid State Communications, Vol. 137, No. 3, 2006, pp. 154-157.
 K. Woan, G. Pyrgiotakis and W. Sigmund, “Photocatalytic Carbon-Nanotube-TiO2 Composites,” Advanced Materials, Vol. 21, No. 21, 2009, pp. 2233-2239.
 Y. Yao, G. Li, S. Ciston, R. M. Lueptow and K. A. Gray, “Photoreactive TiO2/Carbon Nanotube Composites: Synthesis and Reactivity,” Environmental Science & Technology, Vol. 42, No. 13, 2008, pp. 4952-4957.
 No. 1, 1991, pp. 178-190.
 H. Kamisaka, T. Adachi and K. Yamashitaa, “Theoretical Study of the Structure and Optical Properties of CarbonDoped Rutile and Anatase Titanium Oxides,” The Journal of Chemical Physics, Vol. 123, No. 8, 2005, Article ID: 084704. http://dx.doi.org/10.1063/1.2007630
 W. Choi, A. Termin and M. R. Hoffmann, “The Role of Metal-Ion Dopants in Quantum-Sized TiO2: Correlation Between Photoreactivity and Charge-Carrier Recombination Dynamics,” Journal of Physical Chemistry, Vol. 98, No. 51, 1994, pp. 13669-13679.
 H. Wang and J. P. Lewis, “Second-Generation Photocatalytic Materials: Anion-Doped TiO2,” Journal of Physics: Condensed Matter, Vol. 18, No. 2, 2006, pp. 421-434. http://dx.doi.org/10.1088/0953-8984/18/2/006
 J. Pascual, J. Camassel and H. Mathieu, “Fine Structure in the Intrinsic Absorption Edge of TiO2,” Physical Review B, Vol. 18, No. 10, 1978, pp. 5605-5614.
 W. Ren and Z. Ai, “Low Temperature Preparation and Visible Light Photocatalytic Activity of Mesoporous Carbon-Doped Crystalline TiO2,” Applied Catalysis B: Environmental, Vol. 69, No. 3-4, 2007, pp. 138-144.
 M. Barberio, P. Barone, A. Bonanno and A. Oliva, “Synthesis and Characterization of Carbon Nanotubes Wrapped on Anatase Microparticles,” Particle and Particle Systems Characterization, Vol. 28, No. 3-4, 2012, pp. 64-70.
 M. Barberio, P. Barone, V. Pingitore and A. Bonanno, “Optical Properties of TiO2 Anatase—Carbon Nanotubes Composites Studied by Cathodoluminescence Spectroscopy,” Superlattice and Microstructure, Vol. 51, No. 1, 2012, pp. 177-183.
 M. Barberio, P. Barone, A. Imbrogno, V. Pingitore, F. Xu and A. Bonanno, “Optical and Structural Properties of Carbon Nanotube-Rutile Heterostructures,” Journal of Chemistry and Chemical Engineering, Vol. 6, 2012, pp. 199-208.
 F. Gentile, E. Battista, A. Accardo, M. L. Coluccio, M. Asande, G. Perrozziello, G. Das, C. Liberale, F. De Angelis, P. Candeloro, P. Decuzzi and E. Di Fabrizio, “Fractal Structure Can Explain the Increased Hydrophobicity of Nanoporous Silicon Films,” Microelectronic Engineering, Vol. 88, No. 8, 2011, pp. 2537-2540.
 M. Saitou, W. Oshikawa and A. Makabe, “Characterization of Electrodeposited Nickel Film Surfaces Using Atomic Force Microscopy,” Journal of Physics and Chemistry of Solids, Vol. 63, No. 9, 2002, pp. 1685-1689.
 A. M. Skolnik, W. C. Hughes and B. H. Augustine, “A Metallic Surface Corrosion Study in Aqueous NaCl Solutions Using Atomic Force Microscopy (AFM),” The Chemical Educator, Vol. 5, No. 1, 2000, pp. 8-13.
 A. Bonanno, M. Barberio, P. Barone, M. Camarca, D. R. Grosso, R. Vasta, et al., “Changes in Electronic Properties of Carbon Structures by Evaporation and Implantation of Alkali Metals,” Vacuum, Vol. 84, No. 8, 2010, pp. 1025-1028. http://dx.doi.org/10.1016/j.vacuum.2009.10.039
 “NIST XPS Data Base.”
 H. Chermette, P. Pertosa and F. M. Michel-Calendini, “Molecular Orbital Study of Satellites in XPS Spwctra of BaTiO3 and TiO2,” Chemical Physics Letters, Vol. 69, No. 2, 1980, pp. 240-245.