Chlorine-anion doping induced multi-factor optimization in perovskties for boosting intrinsic oxygen evolution

The oxygen evolution reaction (OER) plays a crucial role in many electrochemical energy technologies, and creating multiple beneficial factors for OER catalysis is desirable for achieving high catalytic efficiency. Here, we highlight a new halogen-chlorine (Cl)-anion doping strategy to boost the OER activity of perovskite oxides. As a proof-of-concept, proper Cl doping at the oxygen site of LaFeO₃ (LFO) perovskite can induce multiple favorable characteristics for catalyzing the OER, including rich oxygen vacancies, increased electrical conductivity and enhanced Fe-O covalency. Benefiting from these factors, the LaFeO_2.9-δCl_0.1 (LFOCl) perovskite displays significant intrinsic activity enhancement by a factor of around three relative to its parent LFO. This work uncovers the effect of Cl-anion doping in perovskites on promoting OER performance and paves a new way to design highly efficient electrocatalysts.