Tunable Chemical Grafting of Three-Dimensional Poly (3, 4-ethylenedioxythiophene)/Poly (4-styrenesulfonate)-Multiwalled Carbon Nanotubes Composite with Faster Charge-Carrier Transport for Enhanced Gas Sensing Performance

Hyojae Kim; Yeongseok Jang; Gyeong Won Lee; Seung Yun Yang; Jinmu Jung; Jonghyun Oh

doi:10.3390/s20092470

Tunable Chemical Grafting of Three-Dimensional Poly (3, 4-ethylenedioxythiophene)/Poly (4-styrenesulfonate)-Multiwalled Carbon Nanotubes Composite with Faster Charge-Carrier Transport for Enhanced Gas Sensing Performance

Sensors (Basel). 2020 Apr 27;20(9):2470. doi: 10.3390/s20092470.

Authors

Hyojae Kim¹, Yeongseok Jang², Gyeong Won Lee³, Seung Yun Yang³, Jinmu Jung⁴, Jonghyun Oh⁴

Affiliations

¹ Department of Bio-Nano System Engineering, Jeonbuk National University, Jeonju 54896, Korea.
² Department of Mechanical Design Engineering, Jeonbuk National University, Jeonju 54896, Korea.
³ Department of Biomaterials Science, Life and Industry Convergence Institute, Pusan National University, Miryang 50463, Korea.
⁴ Department of Nano-bio Mechanical System Engineering, Jeonbuk National University, Jeonju 54896, Korea.

Abstract

The three-dimensional volumetric application of conductive poly (3,4-ethylenedioxythiophene)/poly (4-styrenesulfonate) (PEDOT:PSS) to multiwalled carbon nanotubes (MWCNTs) has not been widely reported. In this study, the applicability of the 3D PEDOT:PSS-MWCNT composite for a gas sensor was investigated with different PEDOT:PSS concentrations. The gas-sensing performance of the 3D PEDOT:PSS-MWCNT composites was investigated using ethanol and carbon monoxide (CO) gas. Overall, in comparison with the pristine MWCNTs, as the PEDOT:PSS concentration increased, the 3D PEDOT:PSS-MWCNT composites exhibited increased conductivity and enhanced gas sensing performances (fast response and recovery times) to both ethanol and CO gases. Importantly, although the PEDOT:PSS coating layer reduced the number of sites for the adsorption and desorption of gas molecules, the charge-carrier transport between the gas molecules and MWCNTs was significantly enhanced. Thus, PEDOT:PSS can be chemically grafted to MWCNTs to enhance the connectivity and conductivity of a 3D network, leading to possible applications in gas sensors.

Keywords: carbon nanotubes; casting; electrical properties; surface analysis.