Electronic\nand Atomic Structural Properties Associated\nwith Enhanced Photodegradation Activity in Mo-Doped TiO<sub>2</sub> Nanoparticles

The efficacy and structural evolution of Mo-doped titania\nnanoparticles\n(MTNPs) as advanced photocatalysts for degrading methyl blue (MB)\nare investigated by X-ray absorption spectroscopy (XAS). The 3 wt\n% MTNP, characterized by uniform size and anatase structure, exhibits\nhigher efficiency. The spectral analyses unveiled structural variations\nin the TiO<sub>6</sub> octahedral structure and revealed an active\nsite of the distorted square pyramidal structure symmetry (C<sub>4v</sub>). The in situ XAS spectra illustrate that MTNPs, particularly at\n3 wt % doping, effectively enhanced the hole carriers in Ti 3d orbitals\nwith a charge transfer to Mo 4d orbitals and impeded electron–hole\npair merging, significantly enhancing the photodegradation under light\nillumination. This study deepens our understanding of the crucial\nrole of Mo doping in optimizing TiO<sub>2</sub> nanoparticle performance\nfor efficient environmental remediation, showcasing the potential\nof MTNPs as sustainable photocatalytic materials.