Boosting VOCs photodegradation performance of Co-doped WO3 nanofibers through efficient oxygen activation and localized electric field construction

Exploring efficient photocatalysts for degrading hazardous volatile organic compounds (VOCs) is gaining increasing popularity. Herein, we developed Co-doped WO3 nanofibrous photocatalysts by incorporating Co dopant into the WO3 lattice, where hexavalent W(VI) is replaced with divalent Co(II). This heterovalent substitution causes significant charge rearrangement around the Co dopant, resulting in a localized electric field (LEF) that enhances oxygen adsorption and activation. Such an electric field drives photoexcited electrons to gather at the Co dopant, thereby achieving spatial charge separation. Both the efficient oxygen activation and LEF forming contribute to the production of superoxide radicals. The Co0.8-WO3 nanofibers demonstrated improved photocatalytic oxidation of gaseous HCHO and CH3COCH3 compared to WO3. This study highlights the significant promotion of dopant-induced oxygen adsorption and LEF-induced efficient carrier separation. These findings offer a new direction for developing more efficient photocatalysts using unique doping approaches.