Self-assembled Cofacial Zinc Porphyrin Supramolecular Nanocapsules as tuneable 1O2 Photosensitizers

Abstract

We demonstrate the benefits of using cofacial Zn-porphyrins as structural synthons in coordination‐driven self‐assembled prisms to produce cage‐like singlet oxygen (1O2) photosensitizers with tunable properties. In particular, we describe the photosensitizing and emission properties of palladium‐ and copper‐based supramolecular capsules, and demonstrate that the nature of the bridging metal nodes in these discrete self‐assembled prisms strongly influences 1O2 generation at the Zn-porphyrin centers. The PdII‐based prism is a particularly robust photosensitizer, whereas the CuII self‐assembled prism is a dormant photosensitizer that could be switched to a ON state upon disassembly of the suprastructure. Furthermore, the well‐defined cavity within the prisms allowed encapsulation of pyridine‐based ligands and fullerene derivatives, which led to a remarkable guest tuning of the 1O2 production