Layered double hydroxide-based core-shell nanoarrays for efficient electrochemical water splitting

Electrochemical water splitting is an efficient and clean strategy to produce sustainable energy productions (especially hydrogen) from earth-abundant water. Recently, layered double hydroxide (LDH)-based materials have gained increasing attentions as promising electrocatalysts for water splitting. Designing LDHs into hierarchical architectures (e.g., core-shell nanoarrays) is one of the most promising strategies to improve their electrocatalytic performances, owing to the abundant exposure of active sites. This review mainly focuses on recent progress on the synthesis of hierarchical LDH-based core-shell nanoarrays as high performance electrocatalysts for electrochemical water splitting. By classifying different nanostructured materials combined with LDHs, a number of LDH-based core-shell nanoarrays have been developed and their synthesis strategies, structural characters and electrochemical performances are rationally described. Moreover, further developments and challenges in developing promising electrocatalysts based on hierarchical nanostructured LDHs are covered from the viewpoint of fundamental research and practical applications.