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Abstract Flexible and wearable sensors show enormous potential for personalized healthcare devices by real‐time monitoring of an individual's health. Typically, a single functional material is selected for one sensor to sense a particular physical signal while multiple materials will be selected for multi‐mode sensing. Vertically aligned nanocomposites (VANs) have recently demonstrated various material combinations and novel coupled multifunctionalities that are hard to achieve in any single‐phase material alone, including multiphase multiferroics, magneto‐optic coupling, and strong magnetic and optical anisotropy. Integrating these novel VANs into wearable sensors shows enormous potential in multi‐mode sensing owing to their multifunctional nature. In this work, the transfer of VANs onto polydimethylsiloxane as a novel flexible chemical and pressure sensor is demonstrated. For this demonstration, the classical BaTiO3‐Au VAN with combined plasmonic and piezoelectric properties is used to demonstrate a multi‐sensing mechanism. A thin water‐soluble buffer of Sr3Al2O6serves as a buffer layer for the epitaxial growth and transfer process. The electrical output based on the piezoelectric responses and identifying 4‐mercaptobenzoic acid by surface‐enhanced Raman spectroscopy reveal great potential for free‐standing VANs in a wearable multifunctional sensing platform.
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Fluoropolymer ferroelectrics: Multifunctional platform for polar-structured energy conversion
Ferroelectric materials are currently some of the most widely applied material systems and are constantly generating improved functions with higher efficiencies. Advancements in poly(vinylidene fluoride) (PVDF)–based polymer ferroelectrics provide flexural, coupling-efficient, and multifunctional material platforms for applications that demand portable, lightweight, wearable, and durable features. We highlight the recent advances in fluoropolymer ferroelectrics, their energetic cross-coupling effects, and emerging technologies, including wearable, highly efficient electromechanical actuators and sensors, electrocaloric refrigeration, and dielectric devices. These developments reveal that the molecular and nanostructure manipulations of the polarization-field interactions, through facile defect biasing, could introduce enhancements in the physical effects that would enable the realization of multisensory and multifunctional wearables for the emerging immersive virtual world and smart systems for a sustainable future.
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- Award ID(s):
- 2103196
- PAR ID:
- 10497801
- Publisher / Repository:
- AAAS
- Date Published:
- Journal Name:
- Science
- Volume:
- 380
- Issue:
- 6645
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- eadg0902
- Format(s):
- Medium: X Size: 1.6 MB
- Size(s):
- 1.6 MB
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/science.adg0902
