Double Bonuses Achieved in Single‐Atom Catalysts for Efficient Oxygen Evolution: Enhanced Reaction Kinetics and Reinforced Electrochemical Reconstruction

Abstract Single metal atoms decorated on earth‐abundant transition‐metal‐based supports have attracted intensive attention toward oxygen evolution reaction (OER) due to their decent activity and low cost. However, further optimizing the catalytic performance is severely plagued by the limited active sites. Conventional optimization relies primarily on increasing the metal loading but is extremely difficult. Thus, it is imperative to go beyond the current design paradigms. Herein, it is reported that the anchored highly active single metal atoms can reinforce the electrochemical reconstruction of the supports and thus yield more substrate active sites. Consequently, increased amount of active sites and enhanced intrinsic activity can be readily realized simultaneously. Taking Ni 2 P 4 O 12 decorated with single Ir atoms as a typical example, an extraordinary activity of η 10 = 186 mV and η 100 = 238 mV and robust stability up to 108 h are achieved. Mechanistic study uncovers that the reinforced reconstruction of Ni 2 P 4 O 12 originates from the promoted PO 4 3− leaching by single Ir atoms, which is an intrinsic feature of the supports to achieve such reinforcement. The proposed concept, decorating single metal atoms on supports featured by facile anion leaching, opens a new avenue to the design of practical electrocatalysts for efficient OER.