A tungstophosphate derivative, (Bu4N)3PW11O39[O(SiOH)2] (TBAPW11Si2), with SiOH groups on the surface was synthesized. Furthermore, a mesoporous hybrid silica material, TBAPW11Si2/SBA-15, was synthesized by grafting TBAPW11Si2 into the channels of SBA-15 via the condensation of SiOH groups on both surfaces. It is found that the Keggin units of TBAPW11Si2 remain perfectly in the hybrid material and are anchored onto the pore walls of SBA-15 by covalent linkage. However, the channels of the hybrid sample is partly blocked accompanied with a decrease in the pore volume, pore size and surface area, although the hexagonal packing of channels is mostly preserved. For the photocatalytic degradation of methyl orange, the hybrid material exhibits not only high catalytic activity but also a recycle performance due to the ability of the material against water-leaching.

Key words: polyoxometalate, post-synthesis, SBA-15, mesoporous hybrid material