Strengthening d-p orbital hybridization by fluorine modification for efficient oxygen evolution reaction

To improve the overall efficiency of alkaline water/seawater electrolysis towards green hydrogen product, the development of cost-effective and promising oxygen evolution reaction (OER) catalysts with alkaline and chloride tolerance at the anode of electrolyzers is very necessary. Here, we introduce a mild “two-step dry-wet milling” strategy to realize the throughout lattice doping of F− for F-MnO2 and then the anchoring of atomically-dispersed Ru onto F-MnO2 support via Ru–O/F hybrid bonds. With the strengthening of Mn 3d–O/F 2p hybridization and the negative charge shield of surface F−, the obtained F-MnO2 supported Ru electrocatalysts (F-Ru-MnO2-TH) can show nice OER activity/selectivity relative to the chloride oxidation reaction and present superior Cl− tolerance/corrosion during the OER process. As a result, small overpotentials of 280 and 200 mV for 10 mA cm−2 are observed for F-Ru-MnO2-TH electrocatalysts in alkaline water and simulated seawater, respectively. Interestingly, it can maintain ~100% and over 95% of its initial activity after continuous 200-h and 300-h operation in alkaline media and simulated seawater, respectively, much superior to that of Ru-MnO2 and commercial RuO2.