Response speed of SnO2-based H2S gas sensors with CuO nanoparticles

CuO nanoparticles on sputtered ${\mathrm{SnO}}_2$ thin-film surface exhibit a fast response speed (14 s) and recovery time (61 s) for trace level (20 ppm) ${\mathrm{H}}_2\mathrm{S}$ gas detection. The sensitivity of the sensor ${\text{(S∼2.06×10}}^3)$ is noted to be high at a low operating temperature of 130 °C. CuO nanoparticles on ${\mathrm{SnO}}_2$ allow effective removal of excess adsorbed oxygen from the uncovered ${\mathrm{SnO}}_2$ surface due to spillover of hydrogen dissociated from the ${\mathrm{H}}_2\mathrm{S–CuO}$ interaction.