Direct Pattern Growth of Carbon Nanomaterials by Laser Scribing on Spin-Coated Cu-PI Composite Films and Their Gas Sensor Application.

Yong-Il Ko,Jungtae Nam,Geonhee Lee,A-Rang Jang,Min Jae Kim,Dong Yun Lee,Keun Soo Kim,Jeong-O Lee

doi:10.3390/ma14123388

Abstract

The excellent physical and chemical properties of carbon nanomaterials render them suitable for application in gas sensors. However, the synthesis of carbon nanomaterials using high-temperature furnaces is time consuming and expensive. In this study, we synthesize a carbon nanomaterial using local laser-scribing on a substrate coated with a Cu-embedded polyimide (PI) thin film to reduce the processing time and cost. Spin coating using a Cu-embedded PI solution is performed to deposit a Cu-embedded PI thin film (Cu@PI) on a quartz substrate, followed by the application of a pulsed laser for carbonization. In contrast to a pristine PI solution-based PI thin film, the laser absorption of the Cu-embedded PI thin film based on Cu@PI improved. The laser-scribed carbon nanomaterial synthesized using Cu@PI exhibits a three-dimensional structure that facilitates gas molecule absorption, and when it is exposed to NO2 and NH3, its electrical resistance changes by −0.79% and +0.33%, respectively.

Highlights

Carbon nanomaterials are core materials for a wide range of industries owing to their excellent physical and chemical properties
A 0.1 V direct current (DC) potential was applied to the sensor, and changes in its resistance level were continuously monitored at room temperature and Materials 2021, 14, 3388 atmospheric pressure
As shown in the Vis–NIR spectra in Figure 2a, the PI and Cu-embedded PI thin film (Cu@PI) (10 wt.% of Cu) films demonstrated transmittances of 95.9% and 21.9%, respectively, at a laser wavelength

Summary

Introduction

Carbon nanomaterials are core materials for a wide range of industries owing to their excellent physical and chemical properties. Their molecular adsorption behavior resulting from their high specific surface areas and conductivity enables their application in gas sensors [1,2,3]. Their synthesis typically involves heat treatment at ~1000 ◦C or higher, which involves lengthy processes and undesired costs [4,5,6]. The gas-sensing performance was measured to evaluate the dynamic response to NO2 and NH3 gases using a source meter

Materials and Methods

Gas Sensing

Characterization

Effect of Cu Particles

Gas Sensing Performance

Conclusions