In this work, the structural features and sensor response toward ammonia of a three dimensional (3D)
SWCNTs material covalently functionalised with 1,6-diethynylpyrene were studied. The target SWCNTs
hybrid material was prepared by the reaction of azido substituted SWCNTs with 1,6-diethynylpyrene
containing double terminal alkyne groups via the azide-alkyne Huisgen cycloaddition (Click) reaction.
The structure of the 1,6-diethynylpyrene compound was determined by different spectroscopic methods
such as FT-IR, 1H NMR, MALDI-TOF mass and UV–vis, while its SWCNT-Pyrene 3D hybrid material was
characterized by FT-IR, Raman, UV–vis spectroscopies and thermogravimetric analysis. The morphology
of the hybrid films was investigated by scanning electron microscope (SEM) and transmission electron
microscope (TEM). The sensing performance of the SWCNT-Pyrene 3D hybrid material was studied against
low-concentrations of NH3 in the range of 0.1–40 ppm by measuring changes in the films’ conductivity
at different levels of relative humidity. The reversible electrical sensor response toward ammonia was
observed both in the case of SWCNT and SWCNT-Pyrene 3D hybrid films, however the response values
of SWCNT-Pyrene 3D hybrid film were higher than those of SWCNT.