Dazzling construction and derivation of metal–organic frameworks with layered double hydroxide substrates in environmental field: Insight into synthesis, performance and mechanism

The in-situ construction of metal–organic frameworks (MOFs) on layered double hydroxides (LDHs) substrates and post-processing to obtain environmentally functional materials (MOF@LDH-based materials) with excellent properties have made noteworthy achievements in the field of environmental remediation. MOF@LDH-based materials have been widely used in environmental remediation because they not only inherit the advantages of the parent material but also generate new properties. Herein, how to synthesize MOF@LDH-based materials for various environmental applications will be explored. First, three strategies are summarized to elaborate the in-situ growth processes of MOFs on LDHs, including self-sacrificial templates, the growth of MOFs on pristine LDHs and modified LDHs. Subsequently, the post-processing of MOF@LDHs and the variation of SSA have also received attention. Furthermore, various environmental applications of MOF@LDH-based materials are summarized, including adsorption of organic dyes, heavy metals and radioactive iodine, gases adsorption and separation, advanced oxidation processes (AOPs), catalytic reduction, sensors, photocatalysis, oxidative desulfurization, and extraction. The different mechanisms involved in the various applications are discussed in depth. Finally, future developments of MOF@LDH-based materials are presented.