Abstract:SnO2 nanoparticles mixed with different amounts of gold nanoparticles (GNPs) were synthesized and their CO sensing properties were investigated. The sol-gel method was employed to prepare the initial solution. SEM, TEM, XRD, DLS and spectrophotometry were used to characterize the nanoparticles. The pure sensors showed a response of about 4 to 12.8 for (20-80)×10-6 CO at operating temperature of 340 °C. The response and recovery time at 50×10-6 Co is about 10 and 14 s, respectively. The amount of GNPs optimized was used to create high performance GNP-SnO2 sensors (m(Au)/m(Sn)=3.7663×10-4) and optimal operating temperature was about 260 °C and the response at concentrations of (20-80)×10-6 was 8.3 to 29.5, respectively.

Key words: GNP-SnO2; SnO2; nanoparticles; gas sensor; sol-gel