Sensitive and Rapid Hydrogen Sulfide Sensors Based on Ni Surface Modified BaTi03 Thick Films

摘要

BaTiO_3 (BT) is synthesized by co-precipitation method with surface modification by Ni to improve the sensitivity and tailoring the operating temperature, when the surface modified thick films are exposed to H2S. The thick film sensor is prepared by screen printing technique. Then BaTi03 thick films are surface-modified by Ni, using nickel chloride. Influence of Ni on the film phase composition, microstructure and sensing characteristics is discussed. Dynamic response properties show that the operating temperature of the surface modified BaTi03 thick film is at 100 °C， which is about 250 °C for pure BaTi03. Response time of the sensor is about 10 s while recovery time is 30 s. The selectivity of the sensor elements for H2S against different gases was also discussed.