Application of TiO₂ Photocatalyst for Improving Ozone Generation Efficiency

With a strong oxidizing capability, ozone (O₃) is widely used in industry. However, ozone generators on the market are expensive and require a lot of energy to operate, which remains the bottleneck for the wide applications. In this study, a novel and energy-efficient ozone generation system is developed via the combination of black-TiO₂ photocatalyst and plasma system. Black-TiO₂ catalyst is prepared by calcining commercial TiO₂ catalyst at 550 °C under a nitrogen atmosphere to extend the absorption spectrum to visible light range to improve catalytic activity. The experimental results show that ozone generation efficiency can be greatly increased to 415 g O₃/kWh via combined black-TiO₂ catalyst and plasma with O₂ as the feeding gas. This can be attributed to the fact that black-TiO₂ catalyst with a smaller energy gap is more efficiently activated to form electron–hole pairs in plasma, which can enhance ozone generation. On the other hand, black-TiO₂ catalyst can provide abundant active sites for active O atoms and O₂ molecules to promote O₃ generation. Black-TiO₂ catalyst prepared in this study reveals good stability. Overall, combination of black-TiO₂ catalyst with plasma reveals good ozone generation efficiency and has a good potential for practical applications.