Strengthened ozone adsorption through positive electric field-induced charge migration on various TiO2 crystal surfaces: A mechanistic and theoretical study

This study investigates the enhancement of ozone adsorption on diverse TiO₂ crystal interfaces through an innovative electrochemical modulation approach. The research focuses on the effects of applied electric field strength and reaction sites on ozone interfacial adsorption energies for Ti/Anatase TiO₂ (0 0 1) and Ti/Rutile TiO₂ (1 1 0) interfaces. The findings reveal that positive electric fields significantly enhance ozone adsorption on both interfaces, with adsorption energies increasing by up to 18% for Ti/Anatase TiO₂ (0 0 1) and 15% for Ti/Rutile TiO₂ (1 1 0). Notably, double water molecule sites (≡(H₂O)₂) play a crucial role in this enhancement process. The study demonstrates that the applied electric field alters the charge distribution at the TiO₂ catalytic interface, thereby increasing interfacial charge density and promoting charge migration to ozone. Furthermore, this process leads to enhanced overlap and hybridization between ≡(H₂O)₂ sites and the s and p orbitals of ozone molecules, resulting in the formation of chemical bonds with lower Fermi levels. These comprehensive results demonstrate the broad applicability of the electrochemical interfacial ozone adsorption enhancement method across different crystal types and surfaces. Consequently, this study provides essential data to support the advancement of greener and more energy-efficient heterogeneous catalytic ozonation processes, potentially contributing to significant improvements in ozone-based water treatment technologies.