Modular Polyoxometalate-Layered Double Hydroxide Composites as Efficient Oxidative Catalysts

The exploitation of intercalation techniques in the field of two‐dimensional layered materials offers unique opportunities for controlling chemical reactions in confined spaces and developing nanocomposites with desired functionality. In this study, the exploitation of the novel and facile “one‐pot” anion‐exchange method for the functionalization of layered double hydroxides (LDHs) is demonstrated. As a proof‐of‐concept, we demonstrate the intercalation of a series of polyoxometalate (POM) clusters, Na3[PW12O40]⋅15 H2O (Na3PW12), K6[P2W18O62]⋅14 H2O (K6P2W18), and Na9LaW10O36⋅32 H2O (Na9LaW10) into tris(hydroxymethyl)aminomethane (Tris)‐modified layered double hydroxides (LDHs) under ambient conditions without the necessity of degassing CO2. Investigation of the resultant intercalated materials of Tris‐LDHs–PW12 (1), Tris‐LDH–P2W18 (2), and Tris‐LDH–LaW10 (3) for the degradation of methylene blue (MB), rhodamine B (RB) and crystal violet (CV) has been carried out, where Tris‐LDH–PW12 reveals the best performance in the presence of H2O2. Additionally, degradation of a mixture of RB, MB and CV by Tris‐LDH–PW12 follows the order of CV>MB>RB, which is directly related to the designed accessible area of the interlayer space. Also, the composite can be readily recycled and reused at least ten cycles without measurable decrease of activity. On the double: The tris(hydroxymethyl)aminomethane (Tris)‐modified layered double hydroxides (LDHs) largely facilitate the intercalation of polyoxometalates (POMs), leading to the formation of Tris‐LDH–POM composites. Utilization of the composites for the catalytic degradation of dyes (e.g., methylene blue, MB) in the presence of H2O2 shows high efficiency and selectivity under mild conditions (see figure).