Recent trends in combinative defect engineering and hybridization approach to develop efficient energy-functional layered double hydroxide-based materials

Layered double hydroxides (LDHs) have attracted significant attention for their outstanding performance in renewable energy technologies. However, despite their promising electrochemical and catalytic activities, LDHs face challenges owing to their low electrical conductivity and poor chemical stability. Hybridization with nanostructured materials has emerged as a promising solution, as nanoscale coupling with conductive and robust nano species improves both the conductivity and durability of LDHs. The introduction of crystal defects in nanohybrids enhances interfacial interactions between hybridized components, making the combination of defect engineering and hybridization strategies a valuable approach to maximizing the functionality of LDH materials. This review explores the synergistic benefits of combining defect engineering and hybridization approaches in developing energy-functional LDH-based hybrid materials. An in-depth discussion focuses on the evolution of chemical bonding and electronic structures in LDH components. Various examples of defective LDH-based nanohybrids are presented based on different synthesis methods and application fields. In addition, recent advancements in characterization techniques, including in situ spectroscopic analyses, are highlighted. The correlation between chemical features and defect structure in LDH materials is also discussed, along with the impact of different defect types on their energy-related functionalities. Finally, future research perspectives are provided to guide the design and synthesis of economically feasible, energy-functional materials. In summary, combining defect engineering and hybridization improves the performance of LDH-based materials for energy applications. This review emphasizes the potential of designing cost-effective, energy-functional nanohybrids and suggests that future research should refine synthesis methods and explore advanced characterization to enhance their practical use.