Polydiphenylamine/zeolite Y composite as a sensor material for chemical vapors

Abstract

A composite of nanoscale polydiphenylamine and dealuminated zeolite Y was fabricated to be used as a sensor material for discriminating various kinds of chemical solvent vapors: non-polar solvents, low-polar solvents, and high-polar solvents. Discriminant analysis was used to confirm that the composite could distinguish different chemical solvents. The effects of surfactant type and concentration, dealuminated zeolite Y content on the electrical conductivity, relative response, and selectivity of the composite were investigated. The response and recovery time, and cyclic response of the composite were also investigated. The composite with sodium dodecyl sulfate as a surfactant with 15% (v/v) dealuminated zeolite Y showed a relatively high relative response toward dichloromethane (DCM) vapor. Discriminant analysis confirmed that the response patterns of the composite toward each chemical solvent could be distinguished among non-polar and low-polar solvents, but not high-polar solvents. Moreover, the interaction of the composite and DCM vapor was reversible as confirmed by cyclic response, Fourier transform infrared spectroscopy spectra, and electrostatic force microscopy images. When compared with conventional microscale polydiphenylamine composites, the nanoscale polydiphenylamine composited with dealuminated zeolite Y (DYH80) is a promising sensor material for detecting non-polar and low-polar solvents.