Facile preparation of polyaniline nanofibers modified bentonite nanohybrid for gas sensor application

Abstract

We report the preparation of polyaniline (PAni) nanofibers by in situ intercalative polymerization of anilinium salt absorbed onto the nanoclay layers and modification of bentonite to an efficient nanohybrid gas sensor. The nanohybrid exhibited stable dispersion in different organic solvents like tetrahydrofuran, dimethyl acetamide and dimethyl sulphoxide. The Fourier transform infrared (FTIR) spectroscopic analysis indicated the formation of the benzenoid-quinoid structure of PAni in the nanohybrid. The wide angle X-ray diffraction study confirmed the crystallinity of the PAni nanofibers and the increase of d-spacing of the clay gallery on formation of the nanohybrid. The formation of the PAni nanofibers within the porous nanoclay layer was confirmed by the field-emission scanning electron microscopy. The sensitivity of the nanohybrid-based gas sensor towards toxic gases viz., acetone, benzene, ethanol and toluene was investigated. The nanohybrid gas sensor exhibited a high sensitivity to acetone compared to benzene, ethanol and toluene using ruthenium electrode than the silver electrode. Therefore, the prepared nanohybrid has the potential to be used as a promising gas sensor for the detection of toxic gases.