THE CHARACTERIZATION OF A SnO2–CuO COMPOSITE–TYPE GAS SENSOR HAVING SENSITIVITY FOR H2 GAS

The hydrogen gas sensing properties and the electrical conductivity of SnO2-CuO composites were investigated at the temperature range of 125- 400 oC in air and in 200 ppm H2 gas. Four composite samples of SnO2:CuO with the ratio of 4:1, 3:2, 2:3 and 1:4, respectively, were fabricated in the pellet form by mechanically pressing and sintered at 800 oC for 3 h in air. The electrical conductivity of the composites was found to increase with the increasing content of CuO and the SnO2:4CuO composite showed the highest conductivity value. On the other hand, 2SnO2:3CuO composite was found to have the highest sensitivity to 200 ppm H2 gas and may be suitable for use as a H2 gas sensor