(Giant) A Discotic Mesogenic Near-Infrared Absorbing Dye and Its Application in Photo-Responsive Liquid Crystal Elastomers
作者：Shao, S.; Bao, M.; Chen, R.; Zhang, Z.; Lu, H.; Wang, M.*; Yang, H.*
關鍵字：Organic dye
論文來源：期刊
具體來源：Giant, 2024, 18, 100271.
發表時間：2024年
Near-infrared (NIR)
light-responsive liquid crystal elastomers (LCEs) doped with organic
small-molecule photothermal agents have garnered scientific attention. However,
the challenge remains in designing and synthesizing mesogenic
photothermal dyes with
absorption wavelengths greater than 800 nm. In
this research, we design a novel discotic mesogenic NIR absorbing dye, namely the nickel bis(dithiolene) complex YHD868, and prepare
NIR-responsive LCE/YHD868 composite films. The discotic mesogenic molecule YHD868 possesses a columnar hexagonal mesophase
and exhibits intense NIR absorption at 868 nm, with a photothermal conversion
efficiency of about 27% and a molar extinction coefficient of approximately
30000 M?1·cm?1. Due to the strong NIR absorption
of YHD868, combined with its excellent photothermal stability, the
LCE/YHD868 composite films exhibit remarkable photoresponse and
mechanical properties. Even
at a low doping concentration of 0.2 wt%, the composite film can achieve a tensile strength of 9.8 MPa and an
elongation at break of 165%. Under 880 nm NIR irradiation (3.3 W·cm?2), the film can complete reversible photo-induced shrinking deformation in
just 2 s, with a shrinkage ratio of about 64%. This work offers a new approach for the development of photo-responsive smart soft
materials.