Redox-active polyoxometalate-based crystalline material-immobilized noble metal nanoparticles: spontaneous reduction and synergistic catalytic activity

A 3D eight-connected redox-active polyoxometalate (POM)-based crystalline material, IFMC-101, has been synthesized based on reduced {P4Mo6O31H6}-based tetrameric clusters. IFMC-101 was used as a reducing agent and stabilizer to prepare Au and Pt nanoparticles (NPs) by auto-redox reactions without extra reduction assistance. For the first time, we have demonstrated a new strategy to prepare noble metal NP-loaded POM-based crystalline catalysts. These crystalline catalysts were employed toward the reduction of 4-nitrophenol by NaBH4 and the efficiency of the Au NP-loaded material, Au@IFMC-101, was nearly 9 times higher than that of the POM-based crystalline material, IFMC-101. This result reveals that Au@IFMC-101 exhibits enhanced activity owing to the synergistic catalysis of noble metal NPs and crystalline POM components.