Hollow shell–corona microspheres with a mesoporous shell as potential microreactors for Au-catalyzed aerobic oxidation of alcohols

Abstract

Au-functionalized hollow shell–corona microspheres with a mesoporous shell are proposed as a microreactor for aerobic alcohol oxidation. These microreactors are constructed by template polymerization followed by hydrolysis of the shell-forming polyvinyltriethoxylsilane segment, and contain a hydrophilic corona to keep the microreactors suspended in the aqueous phase and a mesoporous chelate shell to immobilize Au nanoparticles and to increase the permeability of the microreactors. These microreactors have the ability to encapsulate and concentrate reactants, and have been demonstrated to mediate Au-catalyzed aerobic alcohol oxidation, which takes place efficiently in a quasi-homogeneous aqueous solution and under organic–aqueous biphasic conditions, since the reactants are highly concentrated within the microcavity. Other benefits of the microreactors include easy catalyst reuse, low catalyst leaching and long-term stability.