High-Sensitivity Flexible Pressure Sensor-Based 3D CNTs Sponge for Human-Computer Interaction.

Jianli Cui,Huixia Sun,Guirong Shao,Xueli Nan

doi:10.3390/polym13203465

Jianli Cui, Huixia Sun + Show 2 more

Open Access

https://doi.org/10.3390/polym13203465

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Journal: Polymers	Publication Date: Oct 9, 2021
Citations: 14	License type: CC BY 4.0

Affiliation: Yuncheng University, Shanxi University

Abstract

Researchers are showing an increasing interest in high-performance flexible pressure sensors owing to their potential uses in wearable electronics, bionic skin, and human–machine interactions, etc. However, the vast majority of these flexible pressure sensors require extensive nano-architectural design, which both complicates their manufacturing and is time-consuming. Thus, a low-cost technology which can be applied on a large scale is highly desirable for the manufacture of flexible pressure-sensitive materials that have a high sensitivity over a wide range of pressures. This work is based on the use of a three-dimensional elastic porous carbon nanotubes (CNTs) sponge as the conductive layer to fabricate a novel flexible piezoresistive sensor. The synthesis of a CNTs sponge was achieved by chemical vapor deposition, the basic underlying principle governing the sensing behavior of the CNTs sponge-based pressure sensor and was illustrated by employing in situ scanning electron microscopy. The CNTs sponge-based sensor has a quick response time of ~105 ms, a high sensitivity extending across a broad pressure range (less than 10 kPa for 809 kPa−1) and possesses an outstanding permanence over 4000 cycles. Furthermore, a 16-pixel wireless sensor system was designed and a series of applications have been demonstrated. Its potential applications in the visualizing pressure distribution and an example of human–machine communication were also demonstrated.

Highlights

These results prove that sensors based on carbon nanotubes (CNTs) sponge can be successfully applied to tactile detection and mechanical image recognition
The chemical vapor deposition method was employed for the synthesis of a 3D elastic porous CNTs sponge, which was used in the piezoresistive sensor
New conductive pathways come into being at the point of contact between the microfibers of CNTs, which essentially shapes the fundamental theory behind the sensing activity for our piezoresistive sensor

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Some sponge-like structures with highly porous and conductive surfaces are available for piezoresistive sensors. It is, unfortunate that these pristine porous structures have some associated shortcomings. Unfortunate that these pristine porous structures have some associated shortcomings They tend to collapse when subjected to large compressive stress owing to their poor mechanical properties. Most of those reported sponge-like materials enable piezoresistance by a physical coating of conductive materials, but the conductive materials can fall off during compression. We investigated its prospective applications in the measurement of human–computer interaction and pressure distribution

Materials

Synthesis of 3D CNT Sponge

Characterization of CNT Sponge

Force Response Measurement

Wireless Detection of Motion

Results and Discussion

Conclusions