Photocatalytic reduction of methylene blue induced by a commercial titanium precursor in homogeneous phase

This work evaluates the photocatalytic activity of titanium(IV) bis(ammonium lactate) dihydroxide (TiBALDH), an inexpensive commercial precursor and potential alternative to TiO2 nanostructures in heterogeneous pho-tocatalysis, to reduce methylene blue in an aqueous medium. Results show that the titanium precursor without further preparation (other than dilution) shows a high activity for degrading the dye within a few seconds, even at 0.5 mM. The photocatalytic activity is dependent on the concentration, type of radiation, and pH, suggesting the presence of two main concentration-dependent photoreactive species, most likely oxoclusters. Additionally, the homogeneous system is not limited by adsorption processes, as is the case in heterogeneous systems with TiO2 nanoparticles, and it offers greater reusability while avoiding catalyst poisoning. This approach shows the potential for efficient advanced oxidation processes in homogeneous solutions by exploiting the chemical equilibrium of titanium lactate complexes in aqueous solution.

Automated summary

This study evaluates the photocatalytic activity of titanium(IV) bis(ammonium lactate) dihydroxide (TiBALDH) as a potential alternative to TiO2 nanostructures for degrading methylene blue in water. The results show that even at a low concentration of 0.5 mM, the undiluted titanium precursor exhibits high activity in degrading the dye within seconds. The photocatalytic activity is influenced by concentration, radiation type, and pH, indicating the presence of concentration-dependent photoreactive species, possibly oxoclusters. This approach demonstrates the potential for efficient advanced oxidation processes in homogeneous solutions.