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Abstract The demand for the capacitive sensor has attracted substantial attention in monitoring pressure due to its distinctive design and passive nature with versatile sensing capability. The effectiveness of the capacitive sensor primarily relies on the variation in thickness of the dielectric layer sandwiched between conductive electrodes. Additive manufacturing (AM), a set of advanced fabrication techniques, enables the production of functional electronic devices in a single-step process. Particularly, the 3D printing approach based on photocuring is a tailorable process in which the resin consists of multiple components that deliver essential mechanical qualities with enhanced sensitivity towards targeted measurements. However, the availability of photocurable resin exhibiting essential flexibility and dielectric properties for the UV-curing production process is limited. The necessity of a highly stable and sensitive capacitive sensor demands a photocurable polymer resin with a higher dielectric constant and conductive electrodes. The primary purpose of this study is to design and fabricate a capacitive device composed of novel photocurable Polyvinylidene fluoride (PVDF) resin utilizing an LCD process exhibiting higher resolution with electrodes embedded inside the substrate. The embedded electrode channels in PVDF substrate are filled with conductive silver paste by an injection process. The additively manufactured sensor provides pressure information by means of a change in capacitance of the dielectric material between the electrodes. X-Ray based micro CT-Scan ex-situ analysis is performed to visualize the capacitance based sensor filled with conductive electrodes. The sensor is tested to measure capacitance response with changes in pressure as a function of time that are utilized for sensitivity analysis. This work represents a significant achievement of AM integration in developing efficient and robust capacitive sensors for pressure monitoring or wearable electronic applications.
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An efficient way of harvesting mechanoluminescent light: Flexible pressure sensor application
Mechanoluminescent (ML) materials are used for fabricating sensors and other devices such as artificial skin, colorful displays, and energy harvesting devices. However, a key challenge in developing ML-based sensors is the ability to effectively capture and efficiently transmit ML light from the sensing location. Here we report a flexible and sensitive thin film pressure sensor, created using a novel combination of ML material and perovskite. In this work, we adopted a simple lateral type design of a thin pressure sensor primarily consisting of (i) a sensing layer of copper-doped zinc sulfide (ZnS:Cu)/polydimethylsiloxane (PDMS) composite and (ii) a light absorbing layer of perovskite. The mixed halide perovskite, a light absorbing material, fully absorbs the green light emitted from ZnS:Cu. The sensor demonstrated consistent signal output under the mechanical bending test. A thin encapsulation layer of PMMA on the perovskite layer prevents moisture inclusion. This innovative technique of utilizing integrated thin perovskite to efficiently harvest ML light has the potential to open up new avenues for advanced research in ML-perovskite-based sensor systems.
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- Award ID(s):
- 1950500
- PAR ID:
- 10502510
- Publisher / Repository:
- ScienceDirect
- Date Published:
- Journal Name:
- Journal of Luminescence
- Volume:
- 260
- Issue:
- C
- ISSN:
- 0022-2313
- Page Range / eLocation ID:
- 119895
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1016/j.jlumin.2023.119895
