The gas sensing mechanism is based on conductance of the ferrites. The oxygen adsorbed on the surface of the material influences conductance of the ferrite. The amount of oxygen on the surface of the material depends on the particle size, specific area and operating temperature of the sensor. The interaction between the sensing material and gas to be detected determines the gas response. Generally, photocatalytic degradation of organic compounds includes various processes. An electron is excited from the valence band to the conduction band (CB) of metal oxides by absorption of light with...