Inorganic layered ion-exchangers for decontamination of toxic metal ions in aquatic systems

Inorganic layered ion-exchangers have received extensive attention in the field of environmental remediation due to their high chemical, thermal and radiolytic stability, large surface areas, and excellent ion exchange capacities. These materials have been widely investigated as adsorbents for decontamination of toxic metal pollutants, such as heavy metals and nuclear waste related metal ions in aquatic systems. In this review, we describe the most important inorganic layered ion-exchangers including layered double hydroxides, layered metal oxides, and layered metal sulfides in terms of their structural features and ion exchange properties as well as potential applications in remediation of metal polluted aquatic systems. Furthermore, the future challenges and outlooks for these materials are also discussed.