Mesoporous Polyoxometalate-Based Ionic Hybrid As a Triphasic Catalyst for Oxidation of Benzyl Alcohol with H2O2 on Water

A self-assembled mesoporous polyoxometalate-based ionic hybrid catalyst [TMGHA]2.4H0.6PW was prepared by combination of alcohol amino-tethered guanidinium ionic liquid [TMGHA]Cl with Keggin phosphotungstic acid H3PW12O40 (PW). Nitrogen sorption experiment validated the formation of mesostructure with moderate BET surface area, and scanning and transmission electron microscopy (SEM and TEM) showed a fluffy coral-shaped morphology for the hybrid. The contact angle test displayed that the hybrid owned hydrophilic–hydrophobic balanced surface that exhibited well wettability for both water and organic substrate like benzyl alcohol. Therefore, the hybrid can efficiently catalyze the water-mediated triphasic oxidation of benzyl alcohol with H2O2. During the reaction, the triphase catalytic system showed a special “on water” effect mainly due to the suitable mesostructure and surface wettability, thus providing some clues for the preparation of green heterogeneous catalyst.