Light-Enabled Reversible Self-Assembly and Tunable Optical Properties of Photoresponsive Polymers-Ligated Nanoparticles

By judiciously design amphiphilic star-like diblock copolymers comprising inner hydrophilic blocks and outer hydrophobic photoresponsive blocks as nanoreactors, monodisperse plasmonic NPs intimately and permanently capped with photoresponsive polymers were prepared. The size and shape of hairy NPs can be precisely tailored by modulating the length of inner hydrophilic block of star-like diblock copolymers. The perpetual anchoring of photoresponsive polymers on the NP surface renders the attractive feature of self-assembly and disassembly of NPs on demand using light of different wavelengths, as revealed by tunable surface-plasmon resonance absorption of NPs and the reversible transformation of NPs between their dispersed and aggregated states.