HUMIDITY SENSING CHARACTERISTIC OF THE EMD DERIVATIVES

A novel approach for a high-quality humidity sensor is to use certain electrolytic manganese dioxide (EMD) derivatives as the sensing material. Sensors consisting of the low valency oxides (Mn2O3 or Mn3O4) Obtained by thermal decomposition of EMD, show very high humidity sensitivity. Moreover, the electrical conductivity in dry atmosphere and the humidity sensitivity characteristics of these sensors can be greatly improved by mixing a certain amount of MnO2 into the sensor elements. With an optimum ratio of MnO2 to Mn3O4, humidity can be determined over a large range.