Improved naphthalene photodegradation rate of CN/Pt-P25 photocatalyst by effectively tuning Pt chemical states via H2 secondary annealing

Photocatalytic technology holds promising prospects for remediating naphthalene pollution in water bodies. In this work, the CN/Pt-P25 photocatalyst was successfully prepared via photodeposition combined with co-pyrolysis methods, and employed for naphthalene photodegradation under simulated sunlight. The chemical state of Pt was found to have a significant impact on the photocatalytic activity. H 2 secondary annealing effectively tuned Pt chemical states, increasing the proportion of Pt 0 species on the CN/Pt-P25 photocatalyst from 41.91 % to 62.24 %. The improved proportion of Pt 0 species proportion led to a reduction in the bandgap, which induced changes in the band positions and notably enhancing the separation efficiency of photogenerated electron-hole pairs. Under simulated sunlight irradiation, (H 2 ) CN/Pt-P25 photocatalyst achieved complete naphthalene photodegradation within 100 min. Thus, photocatalysts containing a high proportion of Pt 0 species exhibited an improved performance in naphthalene photodegradation. These findings provide new insights into the application of photocatalytic technology for the remediation of PAHs.