Insight of Diversified Reactivity and Theoretical Study of Mixed-Phase Titanium Dioxide for the Photoactivation of Small Molecules

The mixed-phase titanium dioxide (TiO₂) nanoparticles were prepared by two different methods; sonothermal (S) and sonothermal followed by hydrothermal (SH). The TiO₂ prepared by SH has shown a superior hydrogen (H₂) generation via photocatalytic splitting of water (H₂O) and formic acid (FA) as well as photocatalytic reduction of carbon dioxide (CO₂) to methanol (MeOH). The H₂ production rate under UVA from H₂O and FA was 0.02 and 3.91 mmol g⁻¹ h⁻¹ respectively while MeOH formation rate was 1.97 mmol g⁻¹ h⁻¹ from CO₂. The DFT calculations of the reactants and products were also investigated.