Confinement of Cu^II–Phthalocyanine in a Bioinspired Hybrid Nanoparticle‐Assembled Structure Yields Selective and Stable Epoxidation Catalysts

Abstract

Herein, we demonstrate that a bioinspired assembly of silica nanoparticles with polyamines as structure-directing agents similar to that known for the biosilicification of diatoms can pave the way for the efficient encapsulation of sulfonated copper-phthalocyanine in a hybrid microcapsule structure, in which the organic component provides a capable environment for its catalytic activity in epoxidation reactions and the nanoassembled structure imparts stability.

One-pot synthesis of ordered mesoporous Cu-KIT-6 and its improved catalytic behavior for the epoxidation of styrene: Effects of the pH value of the initial gel

“…As an example, Cu(II) acetylacetonate on a core-shell structured Fe3O4@SiO2 presented a styrene conversion of 86.7% and SO selectivity of 51.4%, while requiring a rather complicated preparation process [90]. Cu-phthalocyanine catalysts exhibited 50% styrene conversion during epoxidation, although this required three times the usual amount of TBHP over 24 h, demonstrating a lower utilization rate for the oxidant [91]. Analogously, Cu-doped hydrotalcites exhibited mediocre styrene conversion even at high dosages of TBHP [92].…”

Microcapsule Structure with a Tunable Textured Surface via the Assembly of Polyoxomolybdate Clusters: A Bioinspired Strategy and Enhanced Activities in Alkene Oxidation

“…The polyamines are known to be responsible for biomineralization and the assembly of silica nanoparticles in generating intricately designed shells in diatoms, wherein the organic–inorganic hybrid composition facilitates various biological transformations . In this context, there have been efforts to develop bioinspired polyamine-mediated methods to construct functional materials. − These involve supramolecular aggregation of cationic polyamines in the presence of multivalent anions as a function of the pH in an aqueous medium. The negatively charged PMA clusters are then assembled around these aggregates to form MCs.…”