Effect of Morphology on the Performance of Nb2O5 Catalysts for Thioether Oxidation at Room Temperature under Solvent‐free Conditions

Abstract Nb 2 O 5 catalysts with different morphologies were synthesized and used for thioether oxidation at room temperature under solvent‐free conditions with H 2 O 2 as the oxidant. Selective formation of sulfoxides in good to excellent selectivities was realized using spherical Nb 2 O 5 as the catalysts. Selective formation of sulfones with excellent selectivities was achieved with layered Nb 2 O 5 as the catalysts. Nb 2 O 5 catalysts with different morphologies possessed different surface areas and acid amounts. A non‐radical mechanism with Nb(OO) as the possible reactive oxygen species is proposed for thioether oxidation over spherical or layered Nb 2 O 5 catalysts. Both the spherical and layered Nb 2 O 5 catalysts demonstrated excellent reusability. There were no obvious changes for their catalytic performance after being recycled for ten runs. This study illustrates a means to modulate the catalytic activity for H 2 O 2 ‐based catalytic reactions by changing the catalyst morphology.