Enhanced electrocatalytic oxygen evolution activity in geometrically designed SrRuO3 thin films

TL;DR

This study demonstrates that geometrically designing SrRuO3 thin films with specific surface morphologies significantly enhances their oxygen evolution reaction activity, offering a promising approach for energy conversion catalysts.

Contribution

It introduces a novel surface engineering strategy for SrRuO3 thin films to improve electrocatalytic activity, emphasizing the role of surface morphology and crystal facet orientation.

Findings

Step-textured films on c-plane sapphire show 25 mV lower overpotential.

Surface morphology and crystal facet orientation critically influence OER activity.

Density functional theory supports the active site-dependent enhancement mechanism.

Abstract

For generation of sustainable, clean and highly efficient energy, the electrocatalytic oxygen evolution reaction represents an attractive platform, thus inviting immense research activities in recent years. However, designing the catalyst with enhanced electrocatalytic activity remains one of the major challenges. Here, we examined the oxygen evolution reaction activities of geometrically designed (with and without step-textured morphology) thin films of an electrocatalytically active correlated metallic SrRuO3 perovskite grown on c- and r-plane sapphire substrates. On c-plane sapphire, as compared to the uniform surface, the step-textured films endowed with active Ru-sites show remarkable decrease in the overpotential (25 mV). Interestingly, the behavior is opposite for the r-plane case, highlighting the significance of the active sites, in addition with the polar surface termination of selective crystal facets. Density functional theory calculation confirms the favorable energy reaction pathway for the active site dependent enhancement in OER. Our strategy might pave the way towards designing the surfaces of various oxide thin films for high performance energy conversion based devices.