A Thermochromic Superhydrophobic Surface.
Highly enhanced solid-state thermochromism is observed in regioregular poly(3-hexylthiophene), P3HT, when deposited on a superhydrophobic polymer-SiO2 nanocomposite coating. The conformal P3HT coating on the nanocomposite surface does not alter or reduce superhydrophicity while maintaining its reversible enhanced thermochromism. The polymeric matrix of the superhydrophobic surface is comprised of a blend of poly(vinylidene fluoride-co-hexafluoropropylene) copolymer and an acrylic adhesive. Based on detailed X-ray diffraction measurements, this long-lasting, repeatable and hysteresis-free thermochromic effect is attributed to the enhancement of the Bragg peak associated with the d-spacing of interchain directional packing (100) which remains unaltered during several heating-cooling cycles. We propose that the superhydrophobic surface confines π-π interchain stacking in P3HT with uniform d-spacing into its nanostructured texture resulting in better packing and reduction in face-on orientation. The rapid response of the system to sudden temperature changes is also demonstrated by water droplet impact and bounce back on heated surfaces. This effect can be exploited for embedded thin film temperature sensors for metal coatings.
Smart Materials, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.
Pietro
P
Cataldi
Smart Materials, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.
Ilker S
IS
Bayer
Smart Materials, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.|Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.|Pattern Analysis and Computer Vision (PAVIS), Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.
Roberto
R
Cingolani
Nanochemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.
Sergio
S
Marras
Pattern Analysis and Computer Vision (PAVIS), Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.
Ryad
R
Chellali
Smart Materials, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.
Athanassia
A
Athanassiou