Noncovalent Spiropyran Coatings for Photoinduced Wettability Switching

Abstract EN

The noncovalent binding of spiropyran to candle-soot-covered surfaces is investigated for wettability switching using a coating procedure realized with a drop casting process of using 0.001 mol/L spiropyran in a 5 : 1 toluene-acetone mixture.

Scanning electron microscopy images reveal a resulting surface with spiropyran flakes in the candle soot.

A reversible switching with UV light and blue or green light is achieved, starting from an initial contact angle of 130° ± 9.68°.

The highest contact angle difference is 41° and reversibility has been shown for several switching cycles.

Hence, our methods provide an easy-to-use strategy to generate surfaces with switchable wettability.