The effect of surfactant-free TiO 2 surface hydroxyl groups on physicochemical, optical and self-cleaning properties of developed coatings on polycarbonate

摘要: TiO2 is a prototypical transition metal oxide with physicochemical properties that can be modified more readily through sol–gel synthesis than other techniques. Herein, we report on the change in density of hydroxyl groups surface synthesized surfactant-free nanoparticles water due to varying pH (7.3, 8.3, 9.3 and 10.3) peroxotitanium complex, i.e. amorphous sol, prior refluxing. This resulted colloidal solutions differing crystallinity, nanoparticle size, optical indirect bandgaps photocatalytic activity. It was shown increasing particles coupled low-temperature annealing (90 °C) induced an anatase rutile transformation. Increasing complex interrupted formation phase crystalline as evidenced by intensity increases Raman bands at ∼822 (Ti–O–H) 906 cm−1 (vibrational Ti–O–H) decrease band 150 cm−1 (anatase photonic Eg). Films prepared from higher suspensions showed lower roughness. The reaction rate constants for photo-induced self-cleaning activity films 7.3, 10.3 were estimated 0.017 s−1, 0.014 s−1, 0.007 s−1 0.006 s−1, respectively.