Design, synthesis and photochromism studies of thienyl containing triarylethylene derivatives and their applications in real-time photoresponsive surfaces

Abstract

Thienyl containing triarylethylene derivatives, namely 2ThDpF and 3ThDpF, with photochromic properties have been designed and synthesized. These new photochromic molecules with simple chemical structures show fast-response and striking photochromic behaviors in the solution-state, in the solid-state and in polymer films. Based on 2ThDpF, a real-time and repeatable photoresponsive surface was fabricated. Upon UV-light irradiation for 1 minute, most of the 2ThDpF nano-aggregates on the SiO₂ substrate changed from cone-shaped to hump-shaped and the contact angles of a water droplet drastically increased from 43° to 95° simultaneously. The surface morphology and wettability can easily be reverted by white-light irradiation for 5 minutes. The key issues to affect the real-time morphology and wettability changes are also discussed in-depth based on single-crystal analyses and TDDFT calculations. Therefore, these triarylethylene derivatives with simple molecular structures are attractive in the areas of photochromism and photoresponsive surfaces.