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With the growing importance of environmental protection, the poison gas sensor. The gas sensor using an inorganic semiconductor, it exists the method is complicated and high cost, low precision; organic semiconductor due to the low cost, the film formation process is simple, easy to be compatible with other technologies, and work at room temperature, etc., has become research focus. Polyaniline (PANI) and is one of the typical metal phthalocyanine. The topics to Template Synthesis tetrasubstituted tolyloxy phthalocyanine palladium (PdPc), perchloric acid synthesis by the relevant literature (the HClO 4 ) doped PANI, the two materials Related characterization. Microfabrication technology and mechanical mask technology produced a flat back with a heating resistor Pt electrode. The the heteroaryl Kasei two of the organic semiconductor material is mixed in different proportions (PANI) x (PdPc) 1-x (0 ≤ x ≤ 1), each of the coating process and evaporation coating process is formed on the electrode, to prepare a gas sensor 2 , a concentration of 0.01% of NO the SO 2 of NO, the Cl 2 gas sensing test, looking for the best gas sensing properties of organic semiconductors doped material. Tests show that the doping ratio x = 1/6 of the composite film on a variety of gas have sensitivity, and the sensitivity is good. Coating and evaporation film were characterized by scanning electron microscopy (SEM), were analyzed from two aspects of the film morphology and molecular structure of the sensing mechanism. The the coating PdPc with PANI membrane structure loose mesh stomatal; the evaporation PdPc film was the local mutual Embed distribution of spherical grains of PANI film was needle-like particles are uniformly distributed, the presence of pores. The presence of pores conducive to adsorption and desorption of gases. Orderly poor coating film, the film thickness, a long response time, but high sensitivity; uniform distribution of the evaporation film, the film is thin, low sensitivity, but the response time is short. It also discusses the impact on the membrane gas sensing performance of device structure and detection methods, and other factors, and future development prospects given the outlook. The experimental data show that the principle and the technology is feasible, but its stability and sensitive mechanism needs to be further explored. The other doped proportion by changing technology and other ways to get a better sensitivity. Other characteristics such as selectivity, etc. In addition, with better sensitivity of the composite membrane also requires in-depth studies. Expected to make the different proportions of the hybrid material to achieve the detection of the gas through the sensor array.
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