Candy-like heterojunction nanocomposite of WO 3 /Fe 2 O 3 -based semiconductor gas sensor for the detection of triethylamine.

A highly efficient gas sensor for the detection of triethylamine based on candy-like WO 3 /Fe 2 O 3 nanocomposite was prepared. The control of morphology and sensing performance of n-n heterojunction WO 3 /Fe 2 O 3 nanocomposites were successfully achieved by the modulation of Fe element content. When the ratio of Fe to W is 0.4, the candy-like nanocomposite of WO 3 /Fe 2 O 3 with great performance is obtained. It is interesting that the candy-like nanocomposite of WO 3 /Fe 2 O 3 with a large specific surface area exhibits better selectivity and sensitivity for sensing TEA gases at a lower operating temperature (260 °C) compared with the gas sensor prepared by using WO 3 alone. To verify the feasibility, the sensing mechanism was investigated and real sample tests were conducted and discussed. Finally, a TEA gas sensor with low limit of detection, short response/recovery time (15/162 s), and high sensitivity was developed. In addition, the prepared gas sensor has satisfactory stability and selectivity and has practical application value.