Bionic Artificial Leaves Based on AIE-Active Supramolecular Hydrogel for Efficient Photocatalysis

A novel hydrogel-based biomimetic artificial leaf is fabricated by integrating host-guest interactions with covalent bonding. Specifically, a water-soluble tetraphenylethylene-embedded pillar[5]arene (m-TPEWP5), which exhibits aggregation-induced emission (AIE) property, is synthesized as the host molecule. An amphiphilic guest G is introduced to form a stable complex (HGSM) via non-covalent interactions. Subsequent copolymerization of HGSM with gelatin methacryloyl (GelMA) yields a hydrogel network (HGGelMA), which not only exhibits AIE characteristics but also enables encapsulation of the acceptor eosin Y (ESY), thereby resulting in the construction of an artificial light-harvesting system HGGelMA⊃ESY that serves as a biomimetic leaf. To emulate natural photosynthesis more closely and optimize the utilization of the collected energy, two organic reactions are performed within this artificial leaf: dehalogenation of bromoacetophenone derivatives and coupling of benzylamine. These reactions demonstrate remarkable catalytic activity and recycling ability during the photocatalytic process.