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Abstract Soft-elasticity in monodomain liquid crystal elastomers (LCEs) is promising for impact-absorbing applications where strain energy is ideally absorbed at constant stress. Conventionally, compressive and impact studies on LCEs have not been performed given the notorious difficulty synthesizing sufficiently large monodomain devices. Here, we use direct-ink writing 3D printing to fabricate bulk (>cm 3 ) monodomain LCE devices and study their compressive soft-elasticity over 8 decades of strain rate. At quasi-static rates, the monodomain soft-elastic LCE dissipated 45% of strain energy while comparator materials dissipated less than 20%. At strain rates up to 3000 s −1 , our soft-elastic monodomain LCE consistently performed closest to an ideal-impact absorber. Drop testing reveals soft-elasticity as a likely mechanism for effectively reducing the severity of impacts – with soft elastic LCEs offering a Gadd Severity Index 40% lower than a comparable isotropic elastomer. Lastly, we demonstrate tailoring deformation and buckling behavior in monodomain LCEs via the printed director orientation.
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This content will become publicly available on February 14, 2026
Flexible pyroelectric energy harvesters from nanocomposites of liquid crystal elastomers/lead zirconate titanate nanoparticles
Pyroelectric materials that can generate electric charges when subjected to temperature changes are of interest for renewable energy. However, current flexible pyroelectric energy harvesters suffer from low output. Here, we present a nanocomposite of liquid crystalline elastomer (LCE) and pyroelectric lead zirconate titanate (PZT) nanoparticles and demonstrate a flexible heat harvesting device with high output. The overall pyroelectricity is enhanced by the secondary pyroelectricity generated from the thermal stress imposed on the LCE. Calculations and simulations corroborate with experiments, suggesting that the monodomain LCE/PZT with fixed boundaries offers the most enhancement. At a maximum heating rate of 0.20 kelvin per second, the fixed monodomain film (42.7 weight % PZT) shows an output current of 2.81 nanoamperes and a voltage of 6.23 volts, corresponding to a pyroelectric coefficientpof −4.01 nanocoulombs per square centimeter per kelvin, 49% higher than that of the widely used polyvinylidene fluoride. Our energy harvester can charge capacitors and power electronic devices such as light-emitting diodes.
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- PAR ID:
- 10645635
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 11
- Issue:
- 7
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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