Figure 6
From: Three-dimensional platinum nanoparticle-based bridges for ammonia gas sensing
Gas sensor results. Bridges of Pt are employed for sensing varying concentrations of ammonia gas. Each NH3 concentration is exposed to the bridges for 30 min, and then they recover for 180 min in background of 6.0 N2 gas with no humidity. In (a) cycles of NH3 in N2 gas is introduced in gas sensor setup. In (b) 70% response times are plotted for different NH3 concentrations. Long-time sensor exposure to NH3 is undertaken to attain saturation value of resistance increase; the time taken to reach 70% of this saturation value is termed as T70 response time. (c) Normalized gas response of Pt bridges to various gases is plotted to show the extent of sensor cross sensitivity/selectivity. (d) Effect of background gas without humidity (N2 and air) is studied by observing the NH3 sensor response cycle. The gas sensor response is shown to improve owing to additional oxygen species helping in the NH3 adsorption and thus the sensing mechanism.
