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Abstract The cost‐effective and scalable synthesis and patterning of soft nanomaterial composites with improved electrical conductivity and mechanical stretchability remains challenging in wearable devices. This work reports a scalable, low‐cost fabrication approach to directly create and pattern crumpled porous graphene/NiS2nanocomposites with high mechanical stretchability and electrical conductivity through laser irradiation combined with electrodeposition and a pre‐strain strategy. With modulated mechanical stretchability and electrical conductivity, the crumpled graphene/NiS2nanocomposite can be readily patterned into target geometries for application in a standalone stretchable sensing platform. By leveraging the electrical energy harvested from the kinetic motion from wearable triboelectric nanogenerator (TENG) and stored in micro‐supercapacitor arrays (MSCAs) to drive biophysical sensors, the system is demonstrated to monitor human motions, body temperature, and toxic gas in the exposed environment. The material selections, design strategies, and fabrication approaches from this study provide functional nanomaterial composites with tunable properties for future high‐performance bio‐integrated electronics.
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Colloidal Photonic Crystal Strain Sensor Integrated with Deformable Graphene Phototransducer
Abstract Flexible, architectured, photonic nanostructures such as colloidal photonic crystals (CPCs) can serve as colorimetric strain sensors, where external applied strain leads to a noticeable color change. However, CPCs' response to strain is difficult to quantify without the use of optical spectroscopy. Integration of flexible electrical readout of CPCs' color change is a challenge due to a lack of flexible/stretchable electrical transducers. This work details a colorimetric strain sensor with optoelectrical quantification based on an integrated system of CPCs over a crumpled graphene phototransducer, which optoelectrically quantifies CPCs, response to strain. The hybrid system enables direct visual perception of strain, while strain quantification via electrical measurement of the hybrid system outperforms that of crumpled graphene strain sensors by more than 100 times. The unique combination of a photonic sensing element with a deformable transducer will allow for the development of novel, electrically quantifiable colorimetric sensors with high sensitivity.
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- PAR ID:
- 10374758
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 29
- Issue:
- 33
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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