At room temperature, 18C-silyl-POM makes a reaction system form an emulsion to increase the interface area and improve the catalytic performance.

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The layered double hydroxides (LDH) of Mg 2 AlNi and Mg 3 Al pillared by Keggin-type phosphotungstic acid anion (POM), i.e. Mg 2 AlNi-POM LDH and Mg 3 Al-POM LDH were synthesized by an ion-exchange method. The synthesized POM intercalated LDH compounds were characterized using various techniques such as FTIR, XRD, TGA and BET. The observed results show that the obtained catalysts retain the layer structure of LDH. Compared with the binary Mg 3 Al-POM LDH, the ternary Mg 2 AlNi-POM LDH catalyst indicated a higher thermal and chemical stability. The catalytic activity of the resulting LDH-POM was also assessed in the green oxidation of cyclohexanol with aqueous H 2 O 2 as an oxidant. The Mg 2 AlNi-POM LDH showed a much higher conversion and selectivity for cyclohexanone than the corresponding Mg 3 Al-POM LDH catalyst.

It is significant for the environment that molecular oxygen replaces conventional heavy metal-containing or toxic oxidants to participate in oxidation reactions.