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Abstract Bottom‐up self‐organization of unordered molecules into ordered, spatiotemporal patterns of complex structures through non‐equilibrium reaction–diffusion (RD) processes is ubiquitous in nature across all scales. Unlike many RD processes that typically lead to transient patterns, periodic precipitation reactions governed by the Liesegang phenomenon are distinguished by the formation of stable, permanent structures. This unique characteristic makes them valuable tools in the development of hierarchical multifunctional materials, an area that has seen significant progress in recent decades. This review summarizes the fundamental aspects of the Liesegang phenomenon, focusing on the key characteristics, compositional features, inherent properties, and formation mechanisms of Liesegang patterns in chemical systems, while also highlighting their occurrence in biological and geological settings. We discuss recent advancements in applying periodic precipitation to address global challenges in microelectronics and environmental monitoring, concluding with a forward‐looking perspective on the promising future applications of the Liesegang periodic precipitation in materials science, nanotechnology, medicine, and environmental engineering.
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Self-organization of nanoparticles and molecules in periodic Liesegang-type structures
Chemical organization in reaction-diffusion systems offers a strategy for the generation of materials with ordered morphologies and structural hierarchy. Periodic structures are formed by either molecules or nanoparticles. On the premise of new directing factors and materials, an emerging frontier is the design of systems in which the precipitation partners are nanoparticles and molecules. We show that solvent evaporation from a suspension of cellulose nanocrystals (CNCs) and l -(+)-tartaric acid [ l -(+)-TA] causes phase separation and precipitation, which, being coupled with a reaction/diffusion, results in rhythmic alternation of CNC-rich and l -(+)-TA–rich rings. The CNC-rich regions have a cholesteric structure, while the l -(+)-TA–rich bands are formed by radially aligned elongated bundles. The moving edge of the pattern propagates with a finite constant velocity, which enables control of periodicity by varying film preparation conditions. This work expands knowledge about self-organizing reaction-diffusion systems and offers a strategy for the design of self-organizing materials.
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- Award ID(s):
- 1810513
- PAR ID:
- 10319716
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 7
- Issue:
- 16
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/sciadv.abe3801
