Enhanced OER performance in La2∕3 Sr1∕3CoO3 through surface defect engineering by Ar ion bombardment

The surface energy profile is the most vital parameter for an effective oxygen evolution reaction (OER) catalyst as the moderate absorption/desorption abilities of the oxygen reaction intermediate determine the overall OER performance. In this study, we have decorated the surface of La[Formula: see text]Sr[Formula: see text]CoO 3 (LSCO) through Ar[Formula: see text] bombardment for introducing non-bulk electronic states, and then the OER activity is evaluated. It is found that the OER performance increases monotonously with Ar[Formula: see text] bombardment duration, the LSCO with 20[Formula: see text]s bombardment demonstrates a 1026.4% enhancement compared to the pristine one. Here, simultaneously produced Co and O defects are responsible for this OER improvement after Ar[Formula: see text] bombardment, where the extra Co[Formula: see text] and oxygen vacancy [Formula: see text] are involved in the OER process. Our investigation presents a promising strategy for improving OER performance by decorating the surface electronic structure of both cationic and anionic ions of an OER catalyst.