Self-Assembly of a Semiconductive and Photoactive Heterobimetallic Metal–Organic Capsule

We report the synthesis of a novel metal–organic capsule constructed from six pyrogallol[4]arene macrocycles, which are switched together by 16 Fe^III and 16 Co^II ions. This supramolecular structure is the first instance of a spheroidal heterometallic nanocage assembled through a one-step metal–ligand coordination approach. This new assembly also demonstrates an important proof of concept through the formation of multiple heterometallic metal–metal interactions within the capsule framework. Photophysical and electrochemical studies of self-assembled capsule films indicate their potential as semiconductors. These materials display unexpected photoelectric conversion properties, thus representing an emergent phenomenon in discrete metal–organic supramolecular assemblies.