Synergistic effects of oxygen vacancies and mesoporous structures in amorphous C@TiO₂ for photocatalytic CO₂...

In this study, the theoretical calculations proves that the combination of oxygen vacancy and amorphous carbon films in TiO₂ (V_O-CT) can effectively reduce the energy bandgap and work function. The minimum Gibbs free energies required for the CO₂RR reaction of V_O-CT are 0.20 eV, which is lower than pure TiO₂. The amorphous c@TiO₂ nanomaterials with oxygen vacancy and mesoporous structures (V_O-MCT) are prepared with the P123 surfactant as the template and oxalic acid as an inducer. The electron paramagnetic resonance indicates the presence of abundant oxygen vacancy defects in the samples. UV-vis spectra indicate that the mesoporous structure enhances light absorption capacity. The photocatalytic CO₂ reduction tests show that the highest conversion rates for CH₄ and CO of V_O-MCT are 14 μmol g^-1 h^-1 and 10.66 μmol g^-1 h^-1, respectively. The electron consumption rate of V_O-MCT is 12.43 times higher than that of commercial TiO₂ (P200).