Indium oxide ceramics doped by selenium for one-electrode gas sensors

The influence of Se doping on the operating characteristics of In2O3-based gas sensors was studied. Here, In2O3-based ceramic beads were prepared by sol–gel technology. The Se concentration in the solution used for the synthesis of In2O3 powders was varied in the range 0–10 wt.%. O3 (∼1 ppm), CO (2000 ppm) and H2 (1000 ppm) were used as the test gases. The addition of selenium into the In2O3 matrix was found to be effective in increasing sensor response to the oxidizing gas, ozone. It was posited that this improvement is connected to optimization of the In2O3 ceramic structure.