Recognizing Ti-site coordination geometry in titanium-oxo clusters for enhanced photo-Fenton-like catalysis

This is the authors' abstract. We don't add key points for this paper.

Titanium-based materials have emerged as promising candidates for photo-Fenton-like catalysis, whereas their structural complexities impede precise understanding of the relevant structure-activity relationships. Owing to their well-defined and tunable structures, titanium-oxo clusters appear to be facile models for looking into the photophysical and photochemical processes in Ti–H2O2 systems. Using PTC-3 as a prototype, we interrogated the relationship between Ti-site coordination environments and photo-Fenton-like behaviors. Through integrated in-/ex- situ spectroscopic analyses and theoretical simulations, we elucidated light-driven H2O2 activation on hexa-coordinated and penta-coordinated Ti sites in PTC-3. The superiority of penta-coordinated Ti site was identified, where extended visible-light absorption and promoted electron transfer could synergistically boost the activation of H2O2 into superoxide radicals. This work brightens the role of Ti-site coordination geometry in photo-Fenton-like processes and paves the way for pursuing titanium-based advanced oxidation.