Sensor application and mathematical modeling of new Zn(II) phthalocyanine containing 26-membered tetraoxadithia macrocycle moieties

Abstract

A novel phthalonitrile containing 26-member tetraoxadithia macrocycle moiety was synthesized in a multistep reaction sequence. New zinc(II) phthalocyanine was obtained by the cyclomerization reaction of this macrocyclic phthalonitrile. The novel phthalocyanine and the precursor compounds have been characterized by a combination of 1H and 13C NMR, FT-IR, UV–vis, elemental analysis and MALDI-TOF mass spectral data. 26-membered phthalocyanine was used to fabricate multilayered Langmuir-Blodgett (LB) thin films dedicated to investigating the gas sensing properties of these novel phthalocyanine materials. SEM images of the uncoated substrate, 8-layered and 16-layered LB thin films were compared to observe the successfully transferred layer by layer onto the solid substrates. Sensor parameters such as selectivity, reproducibility, thickness effect, recovery and response rates were examined for highly toxic benzene and toluene vapors using the mass sensitive Quartz Crystal Microbalance (QCM) technique. The first time the thickness effect on the gas sensing mechanism for selected material was also investigated. Validation of the experimental measurements of QCM kinetic was implemented using nonlinear autoregressive with exogenous input neural network for modelling using the frequency shift value. Comparison of these frequency shift of artificial neural network with real-experimental data showed the accuracy of the artificial neural network model.