Synergistic effect of F doping and WO3 loading on electrocatalytic oxygen evolution

• F pollutants are reused in the preparation of F-doped carbon catalysts. • Uniform F doping is achieved by grafting F fragments onto graphite sheet (GS). • The small size of WO 3 are in-situ synthesized and loaded. • The WO 3 @F-doped GS catalyst shows excellent OER activity and stability. • DFT calculation reveals the synergistic effect of F doping and WO 3 loading on OER. Electrochemical oxygen evolution reaction (OER) is an important anodic semi-reaction for energy storage and conversion. In this work, Perfluorooctanoic acid (PFOA), an aqueous pollutant, is degraded into F-containing fragments and captured to prepare ultrasmall WO 3 decorated F-doped graphite sheets (WO 3 @F-GS) via a plasma-induced assembly method. WO 3 @F 0.1 -GS achieves a low overpotential of 298 mV and Tafel slope of 77.6 mV dec -1 , as low as that of RuO 2 . Meanwhile, WO 3 @F 0.1 -GS exhibits good stability in both OER and overall water splitting in 1 M KOH. The synergistic effect of WO 3 and F enhances the electrocatalytic performance. Density functional theory calculations prove W 4+ coordinates with F-doping resulting in enhanced adsorption of OH - and decreased energy barrier of OH deprotonation, leading good activity. The steric hindrance of F and WO 3 loading hinder the stacking of graphitic layers and improve the stability. This work not only provides a mild synthesis strategy of F-doping, but also provides a novel reutilization approach for fluoride waste.