Discrimination of 1- and 2-Propanol by Using the Transient Current Change of a Semiconducting ZnFe2 O4 Chemiresistor

Kalisadhan Mukherjee; Chinedu E Ekuma; Yangyang Zhao; Abhishek Maikap; Sina Najmaei; Mona E Zaghloul

doi:10.1002/cplu.201900036

Discrimination of 1- and 2-Propanol by Using the Transient Current Change of a Semiconducting ZnFe₂ O₄ Chemiresistor

Chempluschem. 2019 Apr;84(4):387-391. doi: 10.1002/cplu.201900036.

Authors

Kalisadhan Mukherjee^{1

2

3}, Chinedu E Ekuma^{4

5}, Yangyang Zhao¹, Abhishek Maikap², Sina Najmaei⁴, Mona E Zaghloul¹

Affiliations

¹ Department of Electrical and Computer Engineering, George Washington University, 800 22nd Street, NW, Washington, DC 20052, USA.
² Centre for Advanced Materials Processing, CSIR-Central Mechanical Engineering Research Institute, Durgapur-, 713209, India.
³ Department of Science School of Technology, Pandit Deendayal Petroleum University Raisan, Gandhinagar, Gujarat, 382077, India.
⁴ U.S. Army Research Laboratory, Sensors and Electron Devices Directorate, 2800 Powder Mill Road, Adelphi, MD 20783, USA.
⁵ Department of Physics, Lehigh University, 16 Memorial Dr East, PA 18015, USA.

PMID: 31939211
DOI: 10.1002/cplu.201900036

Abstract

A semiconducting metal oxide (SMO) chemiresistor (ZnFe₂ O₄ ) is used for discriminating two isomeric volatile organic compounds (VOCs), namely 1- and 2-propanol. The transient current of the SMO chemiresistor is correlated with the aerobic oxidation of organic vapors on its surface. The changes in transient current of the ZnFe₂ O₄ chemiresistor are measured at different temperatures (260-320 °C) for detecting equal concentrations (200 ppm) of the two structural isomers of propanol. The transient current of ZnFe₂ O₄ reflects a faster oxidation of 2-propanol than 1-propanol on the surface. First-principles calculations and kinetic studies on the interaction of 1- and 2-propanol over ZnFe₂ O₄ provide further insight in support of the experimental evidence. The calculations predict more spontaneous adsorption of 2-propanol on the (111) surface of ZnFe₂ O₄ than 1-propanol. Kinetic parameters for the oxidation of isomeric vapors are estimated by modelling the transient current of ZnFe₂ O₄ using the Langmuir-Hinshelwood reaction mechanism. The faster oxidation of 2-propanol and comparatively lower activation energy for the respective process over ZnFe₂ O₄ is justified in accordance to the chemical structures of vapors. The findings have strong implications in exploring a new technique for discriminating isomeric VOCs, which is significant for environmental monitoring and medical applications.

Keywords: chemiresistors; first-principles calculations; isomer discrimination; semiconducting metal oxides; volatile organic compounds.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.