Preparation of meso-tetra(4-pyridyl)porphyrin film for optical gas sensor

摘要

The work presented a simple way to prepare a meso-tetra(4-pyridyl)porphyrin (MTPyP) film for optical gas sensor. The dip-dry coating method that was developed by our reaserch shows a strong absorption band at 418 nm. We also proposed a simple method, peak ratio, to do the semiquantitative analysis of hydrochloric acid (HCI) and ammonia (NH_3) molecules adsorbed on the dip-dry coating MTPyP film by their absorption bands. The MTPyP film was prepared on glass substrate and spectrometer was used to obtain the spectra as sensing the vapor molecules. The ratio of peaks values at 418 nm and 450 nm was used to identify the vapor types and to determine the concentrations. The results show that the peak ratio of HCI is approaching less than one and the peak ratio of NH_3 is always larger than one for two-hour measurment.