초록 |
A simple strategy for light-driven shape transition of block copolymer (BCP) particles is reported in a reversible manner using azobenzene-grafted Au nanoparticles (Au@Azo NPs). The key strategy for the shape transformation of BCP particles is to introduce Au@Azo NPs as surfactants, whose polarity can be changed by photoisomerization according to the light of a specific wavelength. Under the visible light, spherical BCP particles are created with evenly distribution of Au@Azo NPs on the PS-outmost layer. Otherwise, ellipsoidal particles are generated under UV irradiation in which both PS and P2VP blocks are exposed to the particles surface. We note that the Au@Azo NPs can be modulated the interfacial wetting behavior of BCP domains by light irradiation. Furthermore, light-active fluorescence is achieved by the shape transformation of the hybrid particles by adding the dye molecules, allowing shape-dependent non-radiative energy transfer between the dyes and Au@Azo NPs. |