Stable and sensitive amino-functionalized graphene/polyaniline nanofiber composites for room-temperature carbon dioxide sensing

Abstract

This article describes the preparation and characterization of amino-functionalized graphene (AmG)/polyaniline (PANI)/poly(methyl methacrylate) (PMMA) nanofiber mats along with the efficiency of these nanofiber composites as a new material for sensing carbon dioxide (CO₂) gas. The surfaces of the PMMA nanofibers were treated at room temperature by ultraviolet (UV) radiation. AmG/PANI was then deposited on the surfaces of the PMMA nanofibers via chemical oxidative polymerization. It was concluded that UV radiation reduced the hydrophobicity of the PMMA surface through introducing oxidized groups onto the surface. The electrical response of the gas sensor based on the composite nanofibers was investigated at room temperature using various concentrations of CO₂ gas. Compared to the PANI/PMMA nanofibers, the AmG/PANI nanofiber composites displayed a better electrical resistance response to CO₂ at room temperature; the AmG/PANI nanofiber composites exhibited higher sensitivity and faster response times under the same conditions.