Recent advancement in ZnAl-LDH-mediated systems towards photocatalytic energy and environmental applications and piezo polarized photocatalytic reactions: synthesis to application via mechanistic insights

Abstract

ZnAl-layered double hydroxide (ZnAl-LDH) is an emerging robust material that has attracted great attention in the field of photocatalysis and piezo polarization-induced photocatalysis owing to its unique physicochemical properties, including a high specific surface area, tunability in metal cation dispersion, specific catalytic site placement, rapid response to mechanical stress, stability, and environmental-friendliness. However, pristine ZnAl-LDH showed low exciton pair separation efficiency, and low conductivity due to a wide band structure that limits their catalytic efficiency. Modifying the ZnAl-LDH-based materials by adopting various design strategies to form a composite or heterostructure ensures improved surface properties for better catalytic performance, stability, and efficiency. This review emphasizes the recent advancement towards designing ZnAl-LDH-based high-performance catalysts using adopted modification strategies such as doping or defect engineering, interlayer anion modification, structural modulation, heterostructure or composite formation, etc., for improved activity. ZnAl-LDH-based high-performance catalysts boost structural adjustability, stability, and improved conductivity, exposing more active sites, thereby enhancing the catalytic performance. Hence, this review delivers a deep dive into the prospects of ZnAl-LDH-based high-performance materials for photocatalytic water splitting, pollutant degradation, CO₂ reduction, and piezo-polarized induced photocatalytic pollutant degradation. Furthermore, the progression of ZnAl-LDH-based high-performance catalysts with a detailed analysis of best-suited characterization techniques has been systematically reviewed to validate the structural characteristics of high-performance catalysts. The mechanisms described in the photocatalytic processes are also thoroughly reviewed. Lastly, the review highlights the advantages, challenges, and compliance perspective in designing ZnAl-LDH-based high-performance photocatalysts for energy production and environmental applications. This review serves as a gateway for exploiting ZnAl-LDH as components to design advanced catalytic materials for future energy safety and ecological deliverance.