The release of metal ions induced surface reconstruction of layered double hydroxide electrocatalysts

Abstract

Developing highly efficient and affordable oxygen evolution reaction (OER) electrocatalysts is of great significance for the large-scale application of water splitting to produce hydrogen. In the present work, we synthesized NiFeV-LDH with abundant highly active sites for the OER. The evolution of the microstructure, composition, and electrocatalytic activity of NiFeV-LDH was studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray absorption fine structure (XAFS), and electrochemical characterization methods. Results showed that electrochemical activation promotes the release of vanadium and reconstruction of the surface composition. Due to the synergistic effect of iron and vanadium, the derived NiFeV-LDH exhibited excellent OER activity and good stability. This work suggests that the surface reconstruction is an efficient strategy to improve the OER activity.