A transparent CNTs/TiO2 composite film with superhydrophobic and photocatalytic functions self-assembled by liquid-phase deposition

A transparent film of carbon nano-tubes and TiO2 composite (CNTs/TiO2) with superhydrophobic and photocatalytic functions has been successfully fabricated on a glass substrate via a simple chemical liquid phase deposition method with adding CNTs dispersion liquid. The transmittance of CNTs/TiO2 film deposited 16 h on glass substrate is 79% at the wavelength of 550 nm. After surface modified by fluorosilane, the contact angle reaches 160 ± 3° and sliding angle is less than 2°. The photocatalytic activity is much higher than that of a pure TiO2 film as probe tested by UV degradation of methylene blue. Characterized by SEM, TEM, FTIR, AFM and UV-Vis, results show that i) the film has a structure of well-dispersed TiO2 nanoparticles loaded oriented on CNTs with high surface roughness; ii) the formation of Ti-O-C chemical bonding; iii) Ti-O-C chemical bonding acts as a bridge and promotes mutual depositions of CNTs and TiO2, finally constructs hierarchical roughness with special micro- and nano-structures. The formation mechanism of self-assemble during the liquid phase deposition may also be extended to preparation of other CNTs/oxide composite function films.