The distinct role of the flexible polymer matrix in catalytic conversions over immobilised nanoparticles

Polymer resins with immobilized metal nanoparticles represent highly promising materials for attaining intelligent and ecologically friendly catalysts. Control of the dynamic swelling behaviour of the polymer resins enables the on/off-switching of the activity of the encapsulated metal nanoparticles, thereby allowing conversion and selectivity to be controlled at a specific time of the chemical reaction. This paper presents a study on the distinct role of the polymer support. Here, the hydrogenation of nitrobenzene was chosen as a model reaction, and nanoparticles of different metals were taken into account. The course of the reaction revealed the essential role of the polymer resins in controlling the diffusion, in particular of the reagents, to and from the catalytically active sites on the surface of the nanoparticles thereby influencing the catalytic activity of the metal and opening up a new approach to catalytic engineering.