Compliment Graphene Oxide Coating on Silk Fiber Surface via Electrostatic Force for Capacitive Humidity Sensor Applications.

Kook Han,Suck Hong,In Lee,Seungdu Kim,Jong Kim,Wan Hwang,Jung-Ha Kim,Byung Cho

doi:10.3390/s17020407

Abstract

Cylindrical silk fiber (SF) was coated with Graphene oxide (GO) for capacitive humidity sensor applications. Negatively charged GO in the solution was attracted to the positively charged SF surface via electrostatic force without any help from adhesive intermediates. The magnitude of the positively charged SF surface was controlled through the static electricity charges created on the SF surface. The GO coating ability on the SF improved as the SF’s positive charge increased. The GO-coated SFs at various conditions were characterized using an optical microscope, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Raman spectroscopy, and LCR meter. Unlike the intact SF, the GO-coated SF showed clear response-recovery behavior and well-behaved repeatability when it was exposed to 20% relative humidity (RH) and 90% RH alternatively in a capacitive mode. This approach allows humidity sensors to take advantage of GO’s excellent sensing properties and SF’s flexibility, expediting the production of flexible, low power consumption devices at relatively low costs.

Highlights

The onset of the internet of things (IoT) and virtual reality (VR) demands the development of flexible, portable devices [1,2]
The results reveal that the graphene oxide (GO) were were seamlessly seamlessly coated on the surface of the silk fiber (SF) that was rubbed against latex before being soaked in the rubbed against latex before being soaked in the GO solution
Set at thethe absence of of was setsetatat0.0.The results show that high quality was uniformly and seamlessly coated on the rubbed against the results show that high quality GO was uniformly and seamlessly coated on the SL rubbed against latex glove, while the was lightly coated on the rubbed against the glass bar

Summary

Introduction

The onset of the internet of things (IoT) and virtual reality (VR) demands the development of flexible, portable devices [1,2]. Compared to consumption during standby and operation modes [34] It was reported the capacitive conventional conductivity or resistivity sensing, capacitive sensing can dramatically reduce power type is less affected by the temperature variation than the resistive type [35]. This method is consumption during standby and and operation modes [34]. GO-coated SF is presented method is cost-effective since GO can be and cheaply mass-produced, and silk fiber (SF) can for flexible and wearable applications unlike conventional solid detection materials. Were characterized by using an optical microscope, Raman spectroscopy, scanning electron microscopy (SEM), and LCR meter

Materials and Methods

Results and Discussion

Conclusions