Light-Sensitive Microspheres Based on Spherical Assembly of Star-Shaped Chromophores

Abstract

A new star-shaped azobenzene chromophore was synthesized to form micrometer-sized spheres exhibiting stable photoswitching ability. The light-sensitive microspheres were prepared by the spherical assembly of the star-shaped azobenzene chromophores. UV-visible absorption spectroscopy and optical microscopy (OM) experiments were employed to investigate repeated light-induced molecular conformational changes of star-shaped azobenzene molecules in the microspheres and the resulting morphological stability. Photoswitching was repeated stably more than 14 times without any appreciable deterioration in the absorption spectra under repeated UV and visible light irradiation.