Abstract: Three azo polyelectrolytes were successfully fabricated into self-assembled multilayers through a layer-by-layer dipping technique. The surface morphology and its variation with the bilayer growth were investigated with atomic force microscopy(AFM). Thecis-trans isomerization of the self-assembled thin films was studied with UV-Vis spectroscopy and compared with the spin-coated films. PEAPE/PDACand PPAPE/PDACmultilayers show significant photochromic effect upon UVlight irradiation. In dark condition, the rates ofcis-to-trans isomerization depend on the chromophore structure. For polyelectrolytes containing the same chromophores, the azo dyes in self-assembled multilayer recover much faster fromcis totrans isomer than those in spin-coated films.

Key words: Azo polyelectrolytes, Self-assembled multilayer, Trans-cis isomerization, Photo-responsive