Eco-Materials Based on Clay Minerals: Synthesis and Applications in Organic Contaminants Transformation and Heavy Metal Removal

摘要

Clay minerals,consisting of octahedral Al-O and tetrahedral Si-Olayers,typically exist in stacked assemblages.Inspired by the fascinating structural features of clay minerals,we explored their potential in making advanced ecomaterials for environmental purposes as following: 1) Utilizingsmectite clay as supporting template to synthesize smectiteintercalatedzero-valence-iron (ZVI)with particle sizes of ～0.5 nm,showing superior reductive reactivitywith organic contaminants such as nitroaromatics and chlorophenols.[1,2]2) Delaminating natural clay minerals to get low cost silica nanolayers (SNLs) as hard template controlling the morphology of TiO2 nanocrystals,one of most studied photocatalysts.[3] Anatase TiO2 nanocuboids wholly exposed with high-energy {001} and {100} facets were successfully synthesized,and the TiO2 nanocrystals with tunable crystal facets and Ti-defected also show remarkable photocatalytic performance for degradation of chlorophenol.3) Using clay minerals as a uniform dispersion medium to prepare nanosized carbon materials and polymeric composites for removal of heavy metal ions in wastewater.The present work implies that the clay minerals hold potential in preparing ecomaterials for environmental applications.