Core-Shell Nanostructured Ru@Ir-O Electrocatalysts for Superb Oxygen Evolution in Acid

The design of highly active and durable catalysts for the sluggish anodic oxygen evolution reaction (OER) in acid remains an urgent yet challenging goal in water electrolysis. Herein, a core-shell nanostructured Ru@Ir-O catalyst with tensile strains and incorporated oxygens is introduced in the Ir shell that holds an extremely low OER overpotential of 238 mV at 10 mA cm(-2) in acid. The material also shows a remarkable 78-fold higher mass activity than the conventional IrO2 at 1.55 V in 0.5 M H2SO4. Structural characterization and theoretical calculations reveal that the core-shell interaction and tensile strain cause band position shift and charge redistribution. These electronic factors furthermore optimize the bonding strength of O* and HOO* intermediates on the surface, yielding significantly boosted OER activity relative to the conventional IrO2.

Automated summary

In this study, a core-shell nanostructured Ru@Ir-O catalyst with low overpotential and high mass activity for the anodic oxygen evolution reaction (OER) in acid was introduced. The core-shell interaction and tensile strain were found to play a significant role in enhancing the OER activity compared to conventional IrO2.