Design and Development of Amperometric Gas Sensor With Atomic Au–Polyaniline/Pt Composite

Parthojit Chakraborty,Yu-An Chien,Wan-Ting Chiu,Masato Sone,Jiri Janata,Mira Josowicz,Takamichi Nakamoto,Tso-Fu Mark Chang

doi:10.1109/jsen.2020.3002822

Abstract

Rapid advancements in information processing and embedded systems require high selective and fast sensors. Conventional gas sensors are not suitable for the detection of isomers of organic compounds due to cross-sensitivity and the response time being limited by slow chemical kinetics. Amperometric gas sensors using conducting polymers modified with metal catalysts are a suitable and robust system due to many tunable properties. In this paper, conducting polymer polyaniline was electrochemically decorated with clusters containing precisely defined number of gold atoms to function as an electro-catalyst. The modified polymer composite showed fast reaction rate for the electro-oxidation of alcohols in both liquid and gas phases. The number of gold atoms affected the catalytic activity. Cyclic voltammograms were measured and results showed discriminable patterns between n-propanol and iso-propanol even at different gas concentrations. Thus, it was demonstrated that gas sensor arrays can be realized by decorating different number of gold atoms on polyaniline electrodes, to yield defined and different selectivity.

Highlights

G AS sensors have a wide range of modern applications such as their use in breath analysis to detect anomaly in Manuscript received January 27, 2020; revised April 21, 2020; accepted May 29, 2020
In this paper, PANI composite decorated with bi-atomic gold (PANI/Au2) was used as the sensing material for classifying between nPrOH and iPrOH vapors
The composite could be successfully used in both liquid and gas phase and discriminable cyclic voltammograms could be obtained at different concentrations of nPrOH and iPrOH

Summary

Introduction

G AS sensors have a wide range of modern applications such as their use in breath analysis to detect anomaly in Manuscript received January 27, 2020; revised April 21, 2020; accepted May 29, 2020. Conventional gas sensors, are known to face some common challenges such as cross-sensitivity to humidity [2] and amperometric gas sensors are electrochemical type of gas sensors that are a more robust choice due to their several merits [3] in terms of characteristics such as low power, ease of fabrication, and the ability to perform in humid conditions. Such sensor characteristics are attractive, they come at a cost of slow chemical kinetics when operating at room temperature, and sensor microfabrication is often a complicated process [4]. One such conducting polymer is polyaniline (PANI) which has been popular due to its availability in several oxidation states, and which offers a wide range of tunable properties [7], [8]

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Discussion

Conclusion