Merging periodic mesoporous organosilica (PMO) with mesoporous aluminosilica (Al/Si-PMO): A catalyst for green oxidation

Mesoporous aluminosilica is a unique structure for catalysis due to Lewis acidity of aluminum. Here, we design a new catalyst by merging periodic mesoporous organosilica with aluminosilica into its structure instead of mere silica. The employed organosilica bridge in this synthesis is a thiourea based organosiloxane precursor which has a unique feature in supporting catalytically active cations. Therefore, we support Cu2+ ions through these thiourea bridges to generate a catalytically active species along with aluminosilica structure (Cu@Al/Si-PMO-TU). Combining alminosilica with Cu2+ ions led to a synergistic catalytic activity in the aqueous oxidation of dibenzothiophene. Furthermore, the addition of Al3+ as a precursor during the synthesis of PMO causes an enhancement in the mesoporosity and surface area and led to the formation of mesoporous nanofibers. The proposed green bifunctional catalyst is easily recoverable and reusable for several consecutive cycles.