Photoresponsive Materials
Light provides high spatiotemporal resolution to precisely control properties and functions of materials. In close collaboration with Prof. Si Wu, Hefei, we synthesize new photoresponsive polymers and nanoparticles for healable and recyclable materials, reversible adhesives, biomedical applications, energy storage, and light-guided self-assembly. Our goal is to answer fundamental questions of photoresponsive materials and offer perspectives for their future applications.
Photoresponsive azopolymers: Azobenzenes undergo cis-trans isomerization upon irradiation with UV or visible light/heat, respectively. We synthesized new azobenzene-containing polymers that switch the glass transition temperatures upon light irradiation, leading to reversible solid-to-liquid transitions. Therefore, light can be used to heal cracks in azopolymer coatings, reprocess azopolymers, and control their adhesion
Photoresponsive metallopolymers: We use Ru complexes that show ligand photosubstitution as building blocks to construct photoresponsive materials. We prepared photoresponsive amphiphiles, surfaces, and polymer gels using Ru complexes. The Ru-containing amphiphiles showed reversible morphological transitions, which was used for phototherapy. The Ru-containing surfaces showed photoswitchable wettability. The Ru-containing polymers showed photo-controlled reversible crosslinking, which can be reprocessed and healed with light.
NIR photoresponsive materials: We use upconverting nanoparticles as building blocks to construct near-infrared (NIR) light-responsive materials. Upconverting nanoparticles can be combined with azopolymers, Ru-containing polymers and other photoresponsive materials. These NIR light-responsive materials are useful for deep-tissue biomedical applications and photoreactions in bulk materials.
