In situ electrochemical sensing of 2-chloroethyl ethyl sulfide (CEES) a CWA simulant using CuPc/RTIL composite gold electrode

Modified gold electrodes have been used for the in situ electrocatalytic oxidation of blister agent simulant 2-choloroethyl ethyl sulfide (CEES). The preparation of composite film based on copper phthalocyanine (CuPc) and air and water stable room temperature ionic liquid (RTIL) 1-butyl-3 methylpyrrolidinium bis(trifluoromethylsulfonyl) imide was explored on gold (Au) electrode. The present modification indicated one electron involvement in the electrocatalytic oxidation of CEES. A linear response in the oxidation current for CEES was obtained in the range between 1.69 × 10−5 M and 5.07 × 10−4 M with a LOD and LOQ value of 1.69 × 10−6 M and 1.69 × 10−5 M, respectively. Moreover, electrochemical parameters such as diffusion coefficient (1.071 × 10−4 cm2 s−1), heterogeneous rate constant (0.116 s−1), transfer coefficient (0.624) and the number of electron involved (1.0) in the CEES oxidation were deduced from cyclic voltammetry results of the composite film modified electrode. The degradation study was also performed with present modification and the degradation products were analyzed by gas chromatography/mass spectrometry (GC/MS). The modified electrode showed negligible loss in electrochemical activity even when it is stored in ambient conditions. These performance advantages were achieved due to the use of environmentally stable RTIL for the modification. These results are also noteworthy because they provide a basis for additional experiments devoted to obtaining new composite materials with improved performances.