Investigation into the Sensing Process of High-Performance H2S Sensors Based on Polymer Transistors

Abstract

Herein a H2S sensor based on a polymer field-effect transistor is reported and the sensor shows high sensitivity, excellent selectivity, fast response, and good operational stability. A concentration as low as 1 ppb H2 is detectable, which is to date the most sensitive H2S sensor based on organic semiconducting film. Thinning the thickness of active layer does not necessarily improve the sensitivity, but rather leads to the reduction of performance if the thickness is too low. Further analysis proposes a mechanism that the changing rate of absorption and desorption of H2S molecules is different when the thickness of active layer varies, indicating the necessity for thickness optimization.

Keywords: H2S; organic field-effect transistors; polymers; sensing process; sensors.