Structural color coating films composed of an amorphous array of colloidal particles via electrophoretic deposition

It is desirable to fabricate colorful coatings that have nonfading properties and are environmentally friendly. In this study, a novel approach for creating structural color coatings from monodisperse silica particles is presented. The structural color coating films, formed from an array of silica particles with a small amount of black additive, are easily prepared by a simple electrophoretic deposition (EPD) technique. The arrangement of the particle array is controlled by varying the applied voltage and deposition time. The iridescence, that is, the angular dependence, of the structural color dramatically changes with the arrangement of the particle array. A variety of colored coatings can be produced by changing the size of the particles. Structural color coatings on materials with curved surfaces and complicated shapes are also achieved by the EPD method. NPG Asia Materials (2017) 9, e355; doi:10.1038/am.2017.13; published online 10 March 2017