Phthalocyanine Organic Semiconductor for NO₂ Gas Sensor

NO2 gas sensors using various metal phthalocyanines were prepared by vacuum sublimation method at 390oC to test the electrical properties of the sensors in the presence of NO2 gas. Among the sensors prepared in the present study, a lead phthalocyanine(PbPc) thin film showed the best performance and its sensitivity was over 80% at 5 ppm of NO2 gas. The structure of PbPc thin film was a mixture of tri and mono-clinic crystal phases. Optimal operating conditions including response time, cyclic treatment of NO2 gas, and selectivity of various reduction and oxidation gases were developed and examined.