A Volatile Organic Compound Sensor Using Porous Co3O4 Spheres

  • Kim, Tae-Hyung ;
  • Yoon, Ji-Wook ;
  • Lee, Jong-Heun
  • Received : 2016.01.27
  • Accepted : 2016.02.16
  • Published : 2016.03.31


Porous $Co_3O_4$ spheres with bimodal pore distribution (size: 2-3 nm and ~ 30 nm) were prepared by ultrasonic spray pyrolysis of aqueous droplets containing Co-acetate and polyethylene glycol (PEG), while dense $Co_3O_4$ secondary particles with monomodal pore distribution (size: 2-3 nm) were prepared from the spray solution without PEG. The formation of mesopores (~ 30 nm) was attributed to the decomposition of PEG. The responses of a porous $Co_3O_4$ sensor to various indoor air pollutants such as 5 ppm $C_2H_5OH$, xylene, toluene, benzene, and HCHO at $200^{\circ}C$ were found to be significantly higher than those of a commercial sensor using $Co_3O_4$ and dense $Co_3O_4$ secondary particles. Enhanced gas response of porous $Co_3O_4$ sensor was attributed to high surface area and the effective diffusion of analyte gas through mesopores (~ 30 nm). Highly sensitive porous $Co_3O_4$ sensor can be used to monitor various indoor air pollutants.


Gas sensor;$Co_3O_4$;Volatile organic compound;Spray pyrolysis


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Grant : Semiconductor gas sensor array and complex sensor module for detection of driver alcohol within 3 seconds

Supported by : Korea Evaluation Institute of Industrial Technology (KEIT)