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A series of ZrO 2 -based hybrid catalysts functionalized by both organosilica groups and Keggin type heteropolyacid, H 3 PW 12 O 40 /ZrO 2 -Si(Et/Ph)Si and H 3 PW 12 O 40 /ZrO 2 -Si(Ph), with different structural orderings and pore geometries were controllably prepared by a one-pot template-assisted sol-gel cocondensation-hydrothermal treatment route. The pore morphologies, textural properties and acidity of as-prepared hybrid catalysts were characterized by XRD, TEM, nitrogen gas porosimetry, in situ pyridine-FTIR spectroscopy and titration, while the structural integrity of the incorporated functionalities was studied by FT-IR, 31 P MAS NMR, 13 C CP-MAS NMR and 29 Si MAS NMR. As the novel solid acid catalysts, the catalytic performance of as-prepared materials was evaluated by esterification of levulinic acid with various alcohols under mild conditions. Meanwhile, comparative studies were carried out to find out the influences of acidity, porosity and surface hydrophobicity on the catalytic activity of the catalysts. Finally, the recyclability of the catalysts was tested.

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One-step prepared organosulfonic acid-functionalized organosilica hollow nanospheres exhibited excellent catalytic activity and stability in direct synthesis of ethyl levulinate from ethanolysis of biomass-derived furfural alcohol.