Electropolymerization of Phthalocyanine and Corrole Materials for Mass-Based Chemical Sensing and e-Nose Applications

The need for the development of efficient sensing materials and processing methods without compromising device performance for organic sensors is one that is continuously growing. We herein report the fabrication of porphyrinoid polymer-coated piezoelectric quartz microbalance (QMB) sensors. Three materials, para- and ortho-bis(aminophenoxy)SiPc and 5,10,15-tris-(4-aminophenyl)copper corrole, were processed through two electropolymerization techniques, cyclic voltammetry and chronoamperometry, to create sensing films for potential mass-based and electronic nose (e-nose) applications. The QMB sensors were exposed to a variety of different gases (CO, NO, CO₂, and trimethylamine), water, and volatile organic compounds (VOCs) (hexane, toluene, triethylamine, ethanol, pentanol, and acetic acid) to investigate their sensitivity toward each one and studied in parallel to explore their ability to function as an e-nose. The work presented herein demonstrates that although individual sensing materials are not selective toward one particular analyte, their sensing behavior is orthogonal enough from one another to successfully discriminate humidity, alcohols, and Lewis acids/bases when investigated as an e-nose.