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Abstract Direct disposal of used soft electronics into the environment can cause severe pollution to the ecosystem due to the inability of most inorganic materials and synthetic polymers to biodegrade. Additionally, the loss of the noble metals that are commonly used in soft electronics leads to a waste of scarce resources. Thus, there is an urgent need to develop “green” and sustainable soft electronics based on eco‐friendly manufacturing that may be recycled or biodegraded after the devices’ end of life. Here an approach to fabricating sustainable soft electronics is demonstrated where the expensive functional materials can be recycled and the soft substrate can be biodegradable. A stretchable agarose/glycerol gel film is used as the substrate, and silver nanowires (AgNWs) are printed on the film to fabricate the soft electronic circuits. The mechanical and chemical properties of the agarose/glycerol gel films are characterized, and the functionality of the printed AgNW electrodes for electrophysiological sensors is demonstrated. The demonstration of the biodegradability of the agarose/glycerol and the recyclability of AgNWs points toward ways to develop sustainable and eco‐friendly soft electronics.
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Ecofriendly Printing of Silver Nanowires with Cellulose Binder for Highly Robust Flexible Electronics
Abstract Scalable manufacturing of soft electronics with high performance and reliability represents one of the most demanding challenges for the application of soft electronics. Herein, an ecofriendly silver nanowire (AgNW) based ink with cellulose as the binder is reported. The ink properties, annealing condition, and electromechanical properties of the printed electronics are investigated. With a proper annealing process, the hot‐melt binder under high temperatures provides excellent adhesion between the NWs and the substrate, leading to robust electrical performance of the printed AgNWs under mechanical deformation, tape peeling, scratching, and chemical corrosion. The printed AgNWs are demonstrated as flexible temperature sensors due to their temperature‐dependent resistance behavior. The temperature sensors are used to sense touching, respiration, and body temperature. The mechanical robustness and chemical stability of the printed AgNW electronics, without the need of an encapsulation layer, makes them ideal for skin‐mounted electronics applications.
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- Award ID(s):
- 2134664
- PAR ID:
- 10641015
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Electronic Materials
- Volume:
- 11
- Issue:
- 10
- ISSN:
- 2199-160X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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