A Novel calix[4]arene thiourea decorated with 2-(2-Aminophenyl)benzothiazole moiety as highly selective chemical gas sensor for dichloromethane vapor

Abstract

A newly synthesized calix[4]arene thiourea derivative decorated with 2-(2-aminophenyl)benzothiazole unit is selected to take part important role in host-guest interactions of the macrocyclic molecules. p-tert-butylcalix[4]arene dithiourea (C[4]-DT) Langmuir-Blodgett (LB) thin films are prepared and characterized to develop a new sensing element for the detection of seven different organic vapors (dichloromethane, chloroform, acetone, benzene, carbon tetrachloride, toluene and m-xylene). The preparation of C[4]-DT-based thin films onto the different substrates was successfully and uniformly achieved with linear regressions of 0.9971 and 0.9954 for coating onto quartz glass and quartz crystal, respectively. The frequency shift (61.01 Hz) and the mass deposited onto quartz crystal (969.80 ng) were calculated for each layer. The swelling dynamics of C[4]-DT QCM chemical sensor was also illuminated by developing the early time Fick's diffusion equation. The sensing measurements can be concluded that owing to its high sensitivity (6.63 Hz/ppm), fast response and low detection limit (0.45 ppm), this proposed C[4]-DT LB coated sensor is expected to be promising alternative chemical sensor for detection of DCM vapor.