In this work, nitrogen doped carbon fiber loaded copper (Cu/CF-N) sensing electrode and Nafion protonconductor are used to fabricate fuel cell type gas sensors that realize fast response/recovery for SO₂detection atroom temperature. This is the first time that this type of sensor has been used to detect SO₂. We investigated theeffect of Cu content on sensors’ performance, and found that the Cu (20 wt%)/CF based sensor exhibited thehighest response. This can be attributed to the optimal Cu content, which exposes the most active sites. Moreover, nitrogen was doped into electrode material to further improve the performance. Nitrogen atoms enhancethe conductivity of the material and its ability to adsorb SO₂. These are confirmed by the complex impedancemeasurement and TPD analysis. The upgraded Cu/CF-N fuel cell type gas sensor showed a response of-435.6nA to 50 ppm SO₂and a low detection limit of 500 ppb. Significantly, the Cu/CF-N sensor demonstrated shortresponse time (44 s) and recovery time (87 s) at room temperature. Furthermore, with the advantages of nopower consumption, excellent selectivity and good repeatability, the fuel cell type gas sensors have broadprospects in the field of room temperature gas detection.

原文链接：https://www.sciencedirect.com/science/article/pii/S0925400523015721