Bioinspired and bristled microparticles for ultrasensitive pressure and strain sensors

Bing Yin,Tianda Fu,Hongyan Gao,Xiaomeng Liu,Jun Yao

doi:10.1038/s41467-018-07672-2

Abstract

Biological sensory organelles are often structurally optimized for high sensitivity. Tactile hairs or bristles are ubiquitous mechanosensory organelles in insects. The bristle features a tapering spine that not only serves as a lever arm to promote signal transduction, but also a clever design to protect it from mechanical breaking. A hierarchical distribution over the body further improves the signal detection from all directions. We mimic these features by using synthetic zinc oxide microparticles, each having spherically-distributed, high-aspect-ratio, and high-density nanostructured spines resembling biological bristles. Sensors based on thin films assembled from these microparticles achieve static-pressure detection down to 0.015 Pa, sensitivity up to 121 kPa−1, and a strain gauge factor >104, showing supreme overall performance. Other properties including a robust cyclability >2000, fast response time ~7 ms, and low-temperature synthesis compatible to various integrations further indicate the potential of this sensor technology in applying to wearable technologies and human interfaces.

Highlights

Biological sensory organelles are often structurally optimized for high sensitivity
We term it as sea urchin-shaped microparticles (SUSMs)
The highaspect ratio and bristle-like geometry in the spines indicate that similar enhancement in signal transduction and mechanical resilience[21,22] may be obtained in individual spines

Summary

Introduction

Biological sensory organelles are often structurally optimized for high sensitivity. Tactile hairs or bristles are ubiquitous mechanosensory organelles in insects. A hierarchical distribution over the body further improves the signal detection from all directions We mimic these features by using synthetic zinc oxide microparticles, each having spherically-distributed, high-aspect-ratio, and highdensity nanostructured spines resembling biological bristles. The tapering geometry or spine structure confers a clever design that promotes signal transduction for high sensitivity, and protects the bristle from mechanical breaking[21,22]. Introducing nanostructured arms or protrusions on the surface of micro- and nanoparticles helped to promote a 3D spherical distribution in nanostructures for improved performance, yielding low detection limit (e.g., 0.3–1 Pa) and high sensitivity (e.g. 2–9 kPa−1) in pressure sensing[13,14]. The limited aspect ratio (e.g.,

Methods

Results

Conclusion