Quantitative Ethylene Measurements with MOx Chemiresistive Sensors at Different Relative Air Humidities

Sensors (Basel). 2015 Nov 6;15(11):28088-98. doi: 10.3390/s151128088.

Abstract

The sensitivity of two commercial metal oxide (MOx) sensors to ethylene is tested at different relative humidities. One sensor (MiCS-5914) is based on tungsten oxide, the other (MQ-3) on tin oxide. Both sensors were found to be sensitive to ethylene concentrations down to 10 ppm. Both sensors have significant response times; however, the tungsten sensor is the faster one. Sensor models are developed that predict the concentration of ethylene given the sensor output and the relative humidity. The MQ-3 sensor model achieves an accuracy of ±9.2 ppm and the MiCS-5914 sensor model predicts concentration to ±7.0 ppm. Both sensors are more accurate for concentrations below 50 ppm, achieving ±6.7 ppm (MQ-3) and 5.7 ppm (MiCS-5914).

Keywords: chemiresistive sensor; ethylene; linear regression model; relative humidity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chemistry Techniques, Analytical / instrumentation*
  • Chemistry Techniques, Analytical / methods
  • Equipment Design
  • Ethylenes / analysis*
  • Food Analysis
  • Humidity
  • Linear Models
  • Oxides / chemistry*
  • Tin Compounds / chemistry*
  • Tungsten / chemistry*

Substances

  • Ethylenes
  • Oxides
  • Tin Compounds
  • tungsten oxide
  • stannic oxide
  • Tungsten