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Commercial, untreated cotton fabrics have been directly silver coated using one-step electroless deposition and, subsequently, conformally encapsulated with a thin layer of poly(perfluorodecylacrylate) (PFDA) using initiated chemical vapor deposition (iCVD). The surface of these PFDA encapsulated fabrics are notably water-repellent while still displaying a surface resistance as low as 0.2 Ω cm −1 , making them suitable for incorporation into launderable wearable electronics. X-ray photoelectron spectroscopy confirms that the PFDA encapsulation prevents oxidation of the silver coating, whereas unencapsulated samples display detrimental silver oxidation after a month of air exposure. The wash stability of PFDA-encapsulated, silver-coated cotton is evaluated using accelerated laundering conditions, following established AATCC protocols, and the samples are observed to withstand up to twenty home laundering cycles without notable mechanical degradation of the vapor-deposited PFDA encapsulation. As a proof-of-concept, PFDA-Ag cotton is employed as a top and bottom electrode in a layered, all-fabric triboelectric generator that produces voltage outputs as high as 25 V with small touch actions, such as tapping.
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Copper Electrodeposition by Hydrogen Evolution Assisted Electroplating (HEA) for Wearable Electronics
A novel technique called hydrogen evolution assisted (HEA) electroplating, has dramatically shown enhancement to the deposition rate of copper compared to galvanostatic conventional electroplating methods, opening new venues for the direct integration of devices to fabrics leading to the development of useful wearable electronics. HEA can be used for both printing copper tracks on a multi-wall carbon nanotubes (MWCNTs) coated template tracks and soldering surface mount electronic devices (SMD) to such tracks, demonstrating its versatility to be used for specific applications in which fabric mutilation wants to be prevented. However, in this project we studied how copper deposition takes place at different voltage ranges using 1000 Denier Coated Cordura Nylon, Laminated Polyester Ripstop and 100% Virgin Vinyl in the constant presence of the hydrogen evolution technique. Cupric sulfate (CUSO 4 ) and sulfuric acid (H 2 SO 4 ) were used as the medium to allow a lateral deposition over a multi-wall carbon nanotube track of 0.1mm by the application of a voltage ranging between - 0.5V to -2.0V using a potentiostat to employ the cyclic voltammeter technique in order to achieve a uniform deposition. Structure of the fabrics and variation of the copper deposits with respect to the type of fabric used were observed using a scanning electron microscopy (SEM).
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- Award ID(s):
- 1953089
- PAR ID:
- 10209439
- Date Published:
- Journal Name:
- 2020 Pan Pacific Microelectronics Symposium (Pan Pacific)
- Page Range / eLocation ID:
- 1 to 5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.23919/PanPacific48324.2020.9059338
