writer：Shao, S.; Bao, M.; Chen, R.; Zhang, Z.; Lu, H.; Wang, M.*; Yang, H.*
keywords：Organic dye
source：期刊
specific source：Giant, 2024, 18, 100271.
Issue time：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.