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Abstract Despite advances in creating dissipative materials with transient properties, such as hydrogels and active droplets, their application remains confined to temporal changes in structural properties. Developing out‐of‐equilibrium materials whose electronic functions are parameterized by a chemical reaction cycle is challenging. Yet, this class of materials is required to construct biomimetic materials. In contrast to traditional chemical reaction cycles that exploit molecularly dissolved building blocks at thermodynamic equilibrium, we show that fiber structures derived from reactive naphthalene diimide (NDI) building blocks can be used as resting states to form far‐from‐equilibrium conductive hydrogels after the addition of chemical fuels. Upon fueling the NDI‐derived fibers, a dual‐component activation and deactivation pathway is deduced by kinetic analysis and is absent when using a molecularly dissolved resting state. Investigating the solid‐state morphologies of the structures formed throughout the fuel‐driven reaction cycle using cryo‐EM reveals that the resting thermodynamic fibers evolve to transient thicker fibrils and layered superstructures. We show that the transient redox‐active hydrogels exhibit a nearly threefold increase in electrical conductivity upon fuel consumption before reverting to their original value over hours. These far‐from‐equilibrium materials are potential candidates in applications such as programmable biorobotics and chemical computing.
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Precise Control of Dissipative Self‐assembly by Light and Electricity
Abstract Nature‐inspired synthetic dissipative self‐assemblies have attracted much attention recently. However, it remains a major challenge to achieve precise control over dissipative supramolecular assembly structures and functions of self‐contained systems. Here we combine light and electricity as two clean, and spatiotemporally addressable fuels to provide precise control over the morphology for dissipative self‐assembly of a perylene bisimide glycine (PBIg) building block in a self‐contained solution. In this design, electrochemical oxidation provides the positive fuel to activate PBIg self‐assembly while photoreduction supplies the negative fuel to deactivate the system for disassembly. Through programming the two counteracting fuels, we demonstrated the control of PBIg self‐assembly into a variety of assembly morphologies in a self‐contained system. In addition, by exerting light and electrical dual fuels simultaneously, we could create an active homeostasis exhibiting dynamic instability, leading to morphological change to asymmetric assemblies with curvatures. Such precise control over self‐assembly of self‐contained systems may find future applications in programming complex active materials as well as formulating pharmaceutical reagents with desired morphologies.
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- Award ID(s):
- 1904939
- PAR ID:
- 10412843
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 29
- Issue:
- 27
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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