Advances in layered double hydroxide-based ternary nanocomposites for photocatalysis of contaminants in water

Recently, photocatalysis technology has been widely considered as an effective method for solving environmental pollution issues and addressing the energy crisis. Hybrids of layered double hydroxide (LDH) exhibit excellent photocatalytic properties for use in the field of wastewater treatment due to the large interlayer spaces, chemical stability, and low cost. However, pristine LDH suffers from numerous limitations, such as insufficient visible light utilization and a high recombination rate of electron-hole pairs, resulting in degradation of photocatalytic performance. Recent advancements have demonstrated that LDH-based hybrids are suitable nanocomposites for photocatalytic applications when combining LDH with other semiconductors. This article summarizes the progress in the field of LDH-based ternary composites with emphasis on the removal of organic pollutants and heavy metal ions from aqueous media. Moreover, the applications and synthesis of LDH-based ternary composites, including corresponding examples, are discussed. In addition, the interaction mechanisms between photocatalysts and contaminants in water are comprehensively explained. Finally, the review provides insights into the challenges and prospects for the advancement of LDH-based photocatalysts.