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Zheng X, Liu Z, Wang R, Chen A. Bending-Insensitive Intrinsically Flexible Ultraviolet Encoding Devices Based on Piezoelectric Nanogenerator-Supplied Liquid Crystalline Polymer Fabrics. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2202639. [PMID: 35871501 DOI: 10.1002/smll.202202639] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 07/06/2022] [Indexed: 06/15/2023]
Abstract
It is significantly challenging for state-of-the-art wearable electronics to stably monitor physicochemical signals under dynamic motions. Herein, a bending-insensitive, self-powered, and intrinsically flexible UV detector has been realized based on well-designed oriented composite fabrics, consisting of ionic liquid (IL)-containing liquid crystalline polymers (ILCPs) and piezoelectric poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] nanogenerators. The novel composite fabrics establish effective UV illuminance-internal stress-electric signal conversion by coupling resistive and piezoelectric effects, with a fast response time of 190 ms. Particularly, benefiting from the intrinsic flexibility of composite fabrics, the ILCP/P(VDF-TrFE) device can maintain stable performance under dynamic bending even if the frequency is up to 2.5 Hz, with a bending insensitivity of less than 1% performance variation under 1.0 mW cm-2 UV light. Combined with the Internet of Things and the American Standard Code for Information Interchange (ASCII), wearable encoding electronics have been successfully implemented with a printing speed of 3.2 s per character under dynamic bending.
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Affiliation(s)
- Xiaoxiong Zheng
- School of Materials Science and Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing, 100191, P. R. China
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing, 100191, P. R. China
| | - Zhefeng Liu
- School of Materials Science and Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing, 100191, P. R. China
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing, 100191, P. R. China
| | - Rui Wang
- School of Materials Science and Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing, 100191, P. R. China
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing, 100191, P. R. China
| | - Aihua Chen
- School of Materials Science and Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing, 100191, P. R. China
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, No. 37 Xueyuan Road, Haidian District, Beijing, 100191, P. R. China
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Zheng X, Jia Y, Chen A. Azobenzene-containing liquid crystalline composites for robust ultraviolet detectors based on conversion of illuminance-mechanical stress-electric signals. Nat Commun 2021; 12:4875. [PMID: 34385464 PMCID: PMC8360969 DOI: 10.1038/s41467-021-25178-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 07/23/2021] [Indexed: 12/15/2022] Open
Abstract
Wearable ultraviolet (UV) detectors have attracted considerable interest in the military and civilian realms. However, semiconductor-based UV detectors are easily interfered by elongation due to the elastic modulus incompatibility between rigid semiconductors and polymer matrix. Polymer detectors containing UV responsive moieties seriously suffer from slow response time. Herein, a UV illuminance-mechanical stress-electric signal conversion has been proposed based on well-defined ionic liquid (IL)-containing liquid crystalline polymer (ILCP) and highly elastic polyurethane (TPU) composite fabrics, to achieve a robust UV monitoring and shielding device with a fast response time of 5 s. Due to the electrostatic interactions and hydrogen bonds between ILs and LC networks, the ILCP-based device can effectively prevent the exudation of ILs and maintain stable performance upon stretching, bending, washing and 1000 testing cycles upon 365 nm UV irradiation. This work provides a generalizable approach toward the development of full polymer-based wearable electronics and soft robots.
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Affiliation(s)
- Xiaoxiong Zheng
- School of Materials Science and Engineering, Beihang University, Beijing, People's Republic of China
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, People's Republic of China
| | - Yining Jia
- School of Materials Science and Engineering, Beihang University, Beijing, People's Republic of China
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, People's Republic of China
| | - Aihua Chen
- School of Materials Science and Engineering, Beihang University, Beijing, People's Republic of China.
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, People's Republic of China.
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Qu T, Guan S, Zheng X, Chen A. Perpendicularly aligned nanodomains on versatile substrates via rapid thermal annealing assisted by liquid crystalline ordering in block copolymer films. NANOSCALE ADVANCES 2020; 2:1523-1530. [PMID: 36132323 PMCID: PMC9418532 DOI: 10.1039/d0na00057d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 03/03/2020] [Indexed: 06/15/2023]
Abstract
The highly ordered perpendicularly aligned cylindrical and lamellar microdomains within block copolymer (BCP) films have important applications in diverse fields. However, the fast normal orientation of self-assembled nanostructures on arbitrary substrates without tedious pre- and postprocessing has been a challenging issue in manufacturing miniaturized devices. Here, we outline the potential for extending the hierarchical self-assembly within azobenzene-containing PS-b-PMA(Az) films to inherently assist in the formation of normally aligned domains using a rapid thermal annealing process (140 °C for 5 min). Liquid crystalline (LC) mesogens in PS-b-PMA(Az) films self-assemble to form a parallelly aligned sematic phase after thermal annealing, as confirmed by grazing-incidence small-angle X-ray scattering (GISAXS), wide-angle X-ray diffraction (WAXD) and ultraviolet-visible (UV-vis) spectra. This sub-phase contributes to broadening of the PS-cylinder-phase window (0.083 ≤ f PS < 0.49) and ∼12 nm PS cylinder structures. Perpendicular cylinders or lamellae are observed on various substrates, such as silicon wafers, flexible polyethylene terephthalate (PET) sheets and conductive aluminum foils. Additionally, the good reactive ion etching (RIE) rate difference between the two blocks makes these BCPs more attractive for advancing the field of BCP lithographic applications for fabricating flexible microelectronic devices.
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Affiliation(s)
- Ting Qu
- School of Materials Science and Engineering, Beihang University Beijing 100191 P. R. China
| | - Song Guan
- School of Materials Science and Engineering, Beihang University Beijing 100191 P. R. China
| | - Xiaoxiong Zheng
- School of Materials Science and Engineering, Beihang University Beijing 100191 P. R. China
| | - Aihua Chen
- School of Materials Science and Engineering, Beihang University Beijing 100191 P. R. China
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Qu T, Guan S, Zhang C, Zheng X, Zhao Y, Chen A. Liquid crystalline moiety-assisted perpendicular orientation of cylindrical domains within P4VP-b-PMA(Az) films with high aspect ratio. SOFT MATTER 2018; 14:7107-7112. [PMID: 30175354 DOI: 10.1039/c8sm01259h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Block copolymer (BCP) films with perpendicularly aligned cylindrical domains of high aspect ratio have important applications in diverse fields. However, an aspect ratio of the cylinders as high as 200 has rarely been reported so far. Here we demonstrate an efficient route to the formation of normally aligned P4VP cylinders with high aspect ratio surrounded by a matrix of azobenzene-containing block (PMA(Az)) via hierarchical self-assembly. A crisscross structure, consisting of parallelly aligned liquid crystalline (LC) layers and normally aligned self-assembly domains, is expected to assist the formation of well-defined nanostructures. The LC layers in the cylindrical films self-assemble to form smectic phase after solvent annealing, as confirmed by WAXD and UV-vis spectra. We found that the aspect ratio of the vertical P4VP cylinders is up to 200 and the film thickness reaches 6 μm. P4VP is a functional polymer, making this P4VP-b-PMA(Az) film more suitable for advanced filters, multi-nanochannels, nanolithography, and high-density storage media, etc.
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Affiliation(s)
- Ting Qu
- School of Materials Science and Engineering, Beihang University, Beijing, 100191, P. R. China.
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Self-assembly of liquid-crystalline block copolymers in thin films: control of microdomain orientation. Polym J 2018. [DOI: 10.1038/s41428-018-0065-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Spherical Compound Micelles with Lamellar Stripes Self-Assembled from Star Liquid Crystalline Diblock Copolymers in Solution. MACROMOL CHEM PHYS 2017. [DOI: 10.1002/macp.201700148] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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