Unlocking surface and interface engineering of layered double hydroxide (LDH)-based catalysts for efficient catalytic water-splitting: a comprehensive review

Hydrogen production by electrochemical and photocatalytic water splitting is a targeted technique to reshape the global energy landscape and establish a sustainable hydrogen economy. The precious-metal-free catalysts with unique morphological design and diverse compositions are the cornerstone for hydrogen via water splitting. Among numerous newly proposed catalytic designs, the layered double hydroxides (LDHs) have been intensively studied owing to their unique structural design of layered structure, bandgap tunability by doping, single-atom integration, and heterostructure interface, which hold promising results for hydrogen production. However, pure LDH catalysts exhibit slow carrier transport behavior, easy agglomeration, and weak electronic conductivity. Therefore, this review summarizes the recent research on designing LDH derivatives using surface and interface regulation technologies to significantly enhance the electro/photocatalytic water splitting by overcoming the bottlenecks above. Meanwhile, this review highlights the influence of defect engineering, heterojunction interface engineering, heteroatom doping effects, and atomic-level coupling effect used in developing LDH derivatives to improve electrochemical and photocatalytic water splitting. Also, the characterization methods of LDH derivative structures at the forefront are analyzed, and the latest application progress is reviewed. Finally, this review describes the necessary development scenarios and high-quality application potential of LDH derivatives as a critical summary that facilitates future research scopes.