Effects of silica additions on H2S sensing properties of CuO-SnO2 sensors

CuO-SnO2 sensors with and without silica additive were prepared by differen t methods. These were then studied for their response to H2S gas in ambient . The influence of the different procedures adopted for preparation on thei r properties such as resistivity and sensitivity is brought out in the ligh t of microstructural aspects obtained from SEM and surface area measurement s. The response characteristics of the sensors have been accounted for in t erms of p-n junctions formed between CuO and SnO2 particles and modificatio n of the effective surface area due to the presence of porous silica additi ve. (C) 1998 Elsevier Science S.A. All rights reserved.