Visible-light-responsive spherical TiO 2 particles were prepared by the sol–gel method by adding urea as pore-forming agent and tungstophosphoric acid (TPA) in different ratios (20% and 30% w/w) and by annealing at 500°C for 2h. Visible light absorption is probably due to WO x formation (i.e. WO 3 ) resulting from the partial degradation of TPA and evidenced by XPS spectra. Besides, 31 P NMR and XPS results showed evidence about the existence of mostly unaltered TPA within TiO 2 nanoparticles and on their surface, together with lacunar or dimeric species. TPA addition not only affected the optical properties of materials but also produced a strong decrease of their point of zero charge (pH pzc ). Results obtained under UV-A irradiation revealed that aqueous malachite green (MG) solutions were efficiently bleached through the oxidative process of N-demethylation being the TiO 2 powder containing 30% (w/w) of TPA (TiO 2 –TPA–30%) (100% of bleaching in 60min) the most active even than Degussa P-25 (80% of MG bleaching in 60min). On the other hand, when blue-light irradiation was used, TiO 2 –TPA–30% powder also revealed the highest photocatalytic bleaching of MG solutions which, as in the case of UV-A light irradiation experiments, was oxidized through N-demethylation processes. Finally, experiments carried out using blue-light irradiation under N 2 atmosphere showed that aqueous MG solutions were not bleached by TiO 2 powders containing TPA.