Highly Selective Detection of Benzene and Discrimination of Volatile Aromatic Compounds Using Oxide Chemiresistors with Tunable Rh-TiO2 Catalytic Overlayers

Young Kook Moon, Seong Yong Jeong, Young Moo Jo, Yong Kun Jo, Yun Chan Kang, Jong Heun Lee

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)

Abstract

Volatile aromatic compounds are major air pollutants, and their health impacts should be assessed accurately based on the concentration and composition of gas mixtures. Herein, novel bilayer sensors consisting of a SnO2 sensing layer and three different xRh-TiO2 catalytic overlayers (x = 0.5, 1, and 2 wt%) are designed for the new functionalities such as the selective detection, discrimination, and analysis of benzene, toluene, and p-xylene. The 2Rh-TiO2/SnO2 bilayer sensor shows a high selectivity and response toward ppm- and sub-ppm-levels of benzene over a wide range of sensing temperatures (325–425 °C). An array of 0.5Rh-, 1Rh-, and 2Rh-TiO2/SnO2 sensors exhibits discrimination and composition analyses of aromatic compounds. The conversion of gases into more active species at moderate catalytic activation and the complete oxidation of gases into non-reactive forms by excessive catalytic promotion are proposed as the reasons behind the enhancement and suppression of analyte gases, respectively. Analysis using proton transfer reaction-quadrupole mass spectrometer (PTR-QMS) is performed to verify the above proposals. Although the sensing characteristics exhibit mild moisture interference, bilayer sensors with systematic and tailored control of gas selectivity and response provide new pathways for monitoring aromatic air pollutants and evaluating their health impacts.

Original languageEnglish
Article number2004078
JournalAdvanced Science
Volume8
Issue number6
DOIs
Publication statusPublished - 2021 Mar 17

Keywords

  • Rh-TiO
  • benzene
  • bilayer sensor
  • gas sensors
  • volatile aromatic compounds

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Chemical Engineering(all)
  • Biochemistry, Genetics and Molecular Biology (miscellaneous)
  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Highly Selective Detection of Benzene and Discrimination of Volatile Aromatic Compounds Using Oxide Chemiresistors with Tunable Rh-TiO<sub>2</sub> Catalytic Overlayers'. Together they form a unique fingerprint.

Cite this