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Autonomous materials systems from active liquid crystals

Nature Reviews Materials volume 6, pages 437–453 (2021)Cite this article

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Abstract

Liquid crystals (LCs) are ubiquitous in display technologies. The orientational ordering in the nematic phase of LCs gives rise to structural anisotropy, the ability to form topological defects and extraordinary sensitivity to interfacial events — three features that are not found in traditional, isotropic liquids. Active LC systems represent a particular class of active materials, in which some form of energy is transformed and used to generate motion, providing opportunities for new technologies and offering a platform to investigate matter far from equilibrium. In this Review, we discuss recent advances in the field of active LC systems, including natural systems, such as cell colonies, biopolymers and bacteria, and synthetic systems, which mimic the adaptive and autonomous behaviours found in nature. We investigate the properties of defects and flows, examine LC interfaces and emulsions, and discuss active LC colloids and composites. Finally, we highlight future possibilities and applications of active LC systems.

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Fig. 1: Applications of topological defects in passive and active liquid crystals.
Fig. 2: Defect properties in biopolymer-based active liquid crystals.
Fig. 3: Control of active matter through activity or anisotropy patterning.
Fig. 4: Emergent active structures in driven liquid crystals.
Fig. 5: Active LC emulsions and interfaces.
Fig. 6: Pattern formation in active nematics.

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Acknowledgements

The work on active living liquid crystals is supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Division of Materials Science and Engineering. Support from the DOE, BES, Division of Materials Science and Engineering DE-SC0019762 for development of responsive chiral liquid crystals far from equilibrium, from the US Army Research Office (MURI: W911NF-15-1-0568) for design of triggerable materials based on liquid crystals, from the National Science Foundation (NSF) grant DMR-1710318 for development of lyotropic liquid crystal models and from the University of Chicago’s Materials Research Science and Engineering Center for development of activity patterning in active liquid crystals (NSF award DMR-1420709) is also gratefully acknowledged. R.Z. also acknowledges the financial support of the Hong Kong RGC under grant no. 26302320.

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  1. These authors contributed equally: Rui Zhang, Ali Mozaffari.

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  1. Pritzker School of Molecular Engineering, The University of Chicago, Chicago, IL, USA

    Rui Zhang, Ali Mozaffari & Juan J. de Pablo

  2. Department of Physics, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR

    Rui Zhang

  3. Center for Molecular Engineering, Argonne National Laboratory, Lemont, IL, USA

    Juan J. de Pablo

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Zhang, R., Mozaffari, A. & de Pablo, J.J. Autonomous materials systems from active liquid crystals. Nat Rev Mater 6, 437–453 (2021). https://doi.org/10.1038/s41578-020-00272-x

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