Facile synthesis of CoFe2O4 nanoparticles and their gas sensing properties.

In recent years, the use of metal ferrites as sensing materials has aroused more and more interest. However, there is a challenge in the use of cobalt ferrite as ethanol sensor with good gas-sensing properties. In this paper, CoFe 2 O 4 was successfully synthesized by using a facile route. The as-synthesized CoFe 2 O 4 exhibited n-type gas-sensing behavior that the resistance decreases in a reducing gas atmosphere. When applied as sensing materials, CoFe 2 O 4 sensors show good sensitivity to ethanol. At 200 °C working temperature, the response value of CoFe 2 O 4 calcined at 400 °C (CFO-400) sensor to 100 ppm ethanol gas is 110, which is much higher than that of CoFe 2 O 4 ethanol sensor in other studies. Additionally, the CFO-400 sensor shows satisfactory repeatability and stability, as well as high selectivity to ethanol detection compared to other gases. The possible sensing mechanism is investigated in this paper. This work not only displays a facile way to synthesize CoFe 2 O 4 , but also provides potential material for gas sensors in future applications. [Display omitted] • CoFe 2 O 4 nanoparticles were successfully synthesized. • As sensing materials, CoFe 2 O 4 sensors showed good sensitivity to ethanol. • The CoFe 2 O 4 calcined at 400 °C sensor can detect 400 ppb ethanol gas. [ABSTRACT FROM AUTHOR]