Au–polymer hybrid microgels easily prepared by thermo-induced self-crosslinking and in situ reduction

This work presents a facile method to prepare Au–polymer hybrid microgels through thermo-induced self-crosslinking and in situ reduction of a gold precursor. Self-assembly of poly(2-dimethylaminoethyl methacrylate-co-3-(trimethoxysilyl)propyl methacrylate) (P(DMAEMA-co-TMSPMA)) produced particles by heating the P(DMAEMA-co-TMSPMA) solution above the lower critical solution temperature (LCST), which were subsequently cross-linked via the hydrolysis and condensation of the methoxysilyl groups to form microgels. The polymer microgels can be used as a reducing agent for in situ reduction of a gold precursor and a stabilizing agent of gold nanoparticles, leading to the formation of Au–polymer hybrid microgels. The size of the Au–polymer hybrid microgels can be adjusted by varying the concentration of the polymer solution. Furthermore, Au–polymer hybrid microgels were used as a catalyst for the reduction of 4-nitrophenol, which exhibited catalytic performance and reusability towards the reaction.