Highly sensitive and flexible pressure sensors using position- and dimension-controlled ZnO nanotube arrays grown on graphene films

Park, J. B. et al. (2021) Highly sensitive and flexible pressure sensors using position- and dimension-controlled ZnO nanotube arrays grown on graphene films. NPG Asia Materials, 13, 57. (doi: 10.1038/s41427-021-00324-w)

Abstract

A facile and novel technique for the fabrication of pressure sensors is reported based on the hybridization of one-dimensional nanomaterials and two-dimensional graphene film. In particular, piezoelectric pressure sensors are fabricated by using vertically aligned and position- and dimension-controlled ZnO nanotube arrays grown on graphene layers. Graphene layers act not only as substrates for catalyst-free growth of high-quality ZnO nanotubes but also as flexible conduction channels connecting ZnO nanotubes and metal electrodes. Freestanding and flexible sensors have been efficiently obtained via mechanical lift-off of hybrid ZnO nanotube/graphene film structures and by exploiting the weak van der Waals forces existing between the graphene film and the original substrates. A prototype of such devices shows a high pressure sensitivity (−4.4 kPa−1), which would enable the detection of weak flows of inert gas. The relatively low wall thickness and large length of the ZnO nanotubes suggest a relatively high sensitivity to external pressures. The obtained nanotube sensors are attached to the philtrum and wrist of a volunteer and used to monitor his breath and heart rate. Overall, the prototype hybrid sensing device has great potential as wearable technology, especially in the sector of advanced healthcare devices.

• Item Type: Articles
• Additional Information: This work was financially supported by the Samsung Research Funding Center of Samsung Electronics (SRFC-TA1803-02(0417-20180116)).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Ghosh, Dr Ramesh

Creator Roles

Ghosh, R.: Methodology, Formal analysis, Investigation, Writing – review and editing

• Authors: Park, J. B., Song, M. S., Ghosh, R., Saroj, R. K., Hwang, Y., Tchoe, Y., Oh, H., Baek, H., Lim, Y., Kim, B., Kim, S.-W., and Yi, G.-C.
• College/School: College of Science and Engineering > School of Engineering > Biomedical Engineering
• Journal Name: NPG Asia Materials
• Publisher: Nature Research
• ISSN: 1884-4049
• ISSN (Online): 1884-4057
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in NPG Asia Materials 13: 57
• Publisher Policy: Reproduced under a Creative Commons License