Journal of Catalysis, Vol.331, 49-56, 2015
Polymer catalyst with self-assembled hierarchical access for sortable catalysis
This study aimed at the present challenge in self-controlled catalysis, addressing how to furnish the catalysts with sortable catalytic ability. This objective was reached by developing a polymer catalyst made of metal nanoparticles and a unique polymer carrier containing self-assembled hierarchical access. The hierarchical access, by closing, relaxing and opening, acted as a molecular switch for providing sequenced entrance to the encapsulated metal nanoparticles. This polymer catalyst showed poor catalytic reactivity at relatively low temperatures due to the closed access, which blocked substrate from the encapsulated metal nanoparticles. This polymer catalyst showed, however, significant reactivity for small molecules of substrate at modest temperatures, arising from relaxing of the access, which allowed small molecules to gain entrance to the catalytic metal nanoparticles. This polymer catalyst further showed significant reactivity for large molecules of substrate at relatively high temperatures, in response to the opening at the access. In this way, this polymer catalyst demonstrated the sortable catalytic ability. This suggested protocol opens up the opportunity to develop smart catalysts for controlled chemical processes. (C) 2015 Elsevier Inc. All rights reserved.