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Sensitive and flexible pressure sensors have invoked considerable interest for a broad range of applications in tactile sensing, physiological sensing, and flexible electronics. The barrier between high sensitivity and low fabrication cost needs to be addressed to commercialize such flexible pressure sensors. A low-cost sacrificial template-assisted method for the capacitive sensor has been reported herein, utilizing a porous Polydimethylsiloxane (PDMS) polymer and a multiwalled carbon nanotube (MWCNT) composite-based dielectric layer. The sensor shows high sensitivity of 2.42 kPa−1 along with a low limit of detection of 1.46 Pa. The high sensitivity originates from adding MWCNT to PDMS, increasing the composite polymer’s dielectric constant. Besides this, the pressure sensor shows excellent stability at a cyclic loading of 9000 cycles, proving its reliability for long-lasting application in tactile and physiological sensing. The high sensitivity of the sensor is suitable for the detection of small deformations such as pulse waveforms as well as tactile pressure sensing. In addition, the paper demonstrates a simultaneous contact and non-contact sensing capability suitable for dual sensing (pressure and proximity) with a single data readout system. The dual-mode sensing capability may open opportunities for realizing compact systems in robotics, gesture control, contactless applications, and many more. The practicality of the sensor was shown in applications such as tactile sensing, Morse code generator, proximity sensing, and pulse wave sensing.
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This content will become publicly available on October 27, 2026
A Graphene-Quantum-Dot Ink-Printed Dual-Mode Bending Sensor for Biomedical Applications
The increasing demand for non-invasive, continuous, and user-friendly healthcare solutions is accelerating the development of advanced biomedical sensors. Flexible optoelectronic sensors, in particular, offer real-time, contactless physiological monitoring for applications such as smart health systems, remote diagnostics, and wearable devices. In this study, the fabrication and characterization of a dual-mode flexible bending sensor is presented that integrates graphene quantum dots with inkjet-printed silver interdigitated electrodes on a polyethylene terephthalate substrate. The sensor exhibits significant strain sensitivity, with the gauge factor increasing with decreasing bending diameter, demonstrating high responsiveness to mechanical deformation. Additionally, the photoluminescence emission peak shifts from 500 nm to 464 nm under strain, providing an optical strain-sensing mode. The sensor’s stable dual-mode (electrical and optical) response across repeated bending cycles enhances its reliability and application versatility. This combined functionality makes the proposed sensor a promising candidate for wearable biomedical platforms that require real-time strain detection and contactless physiological monitoring.
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- Award ID(s):
- 2430440
- PAR ID:
- 10630895
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3315-7510-6
- Page Range / eLocation ID:
- 295 to 299
- Format(s):
- Medium: X
- Location:
- Rome, Italy
- Sponsoring Org:
- National Science Foundation
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