Temperature-Regulated Bidirectional Capillary Force Self-Assembly of Femtosecond Laser Printed Micropillars for Switchable Chiral Microstructures

作者：Wu, Dong; Ni, Caiding; Lao, Zhaoxin^*; Cao, Yang; Ni, Jincheng; Ren, Zhongguo; Liu, Shunli; Tao, Yuan; Xin, Chen; Pan, Deng; Hu, Yanlei^*; Chu, Jiaru

来源：ACS Nano, 2023, 17(13): 12820-12828.

DOI：10.1021/acsnano.3c04181

• self-assembly
• capillaryforces
• chiral microstructures
• femtosecond laser
• two photon polymerization

Bottom-up self-assembly is regardedas an alternativeway to manufactureseries of microstructures in many fields, especially chiral microstructures,which attract tremendous attention because of their optical micromanipulationsand chiroptical spectroscopies. However, most of the self-assembledmicrostructures cannot be tuned after processing, which largely hinderstheir broad applications. Here, we demonstrate a promising manufacturingstrategy for switchable microstructures by combining the flexibilityof femtosecond laser printing induced capillary force self-assemblyand the temperature-responsive characteristics of smart hydrogels.Through designing asymmetric cross-link density, the printed microarchitecturescan be deformed in the opposite direction and assembled into switchableordered microstructures driven by capillary forces under differenttemperatures. Finally, the assembled chiral microstructures with switchableopposite handedness are realized, which shows tunable vortical dichroism.The proposed strategy holds potential applications in the fields ofchiral photonics, chiral sensing, and so on.

• 单位
  中国科学院