Fabrication of polyaniline–graphene oxide hybrid nanocomposites by green interfacial polymerization for all-solid-state supercapacitors and enzymatic glucose sensors

Abstract

An interfacial polymerization-based green approach was developed for the synthesis of polyaniline–graphene oxide (PANI-GO) nanocomposites. Instead of the commonly used organic solvents such as CHCl₃, CCl₄, hexane and toluene, vegetable oil was used here as the organic phase. Thus, the prepared nanocomposite was characterized by Fourier-transform infrared spectroscopy (FTIR), UV-visible spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA) techniques. The scanning electron microscopy (SEM) examinations revealed the formation of a uniform coating of PANI fibers on the surface of GO sheets. The PANI-GO composite showed pseudocapacitive behavior with a high specific capacitance of 510 F g⁻¹ at a current density of 1 A g⁻¹. The specific energy and specific power of the PANI-GO electrode material were calculated to be 45.3 W h kg⁻¹ and 407.9 W kg⁻¹, respectively, which maintained 92% stability even after completing 1000 cycles at a current density of 30 A g⁻¹. Furthermore, the solid-state symmetric supercapacitor of the PANI-GO nanocomposite yielded an areal capacitance of 143.6 mF cm⁻² at a current density of 1 mA cm⁻². The symmetric supercapacitor maintains 76% of its initial areal capacitance after 4000 cycles. The PANI-GO nanocomposite was also explored for the fabrication of enzymatic glucose sensors. The amperometric response of PANI-GO indicates that the enzyme-loaded electrode material exhibited good catalytic activity towards the oxidation of glucose in the linear range of 20–80 μM. The limit of detection was found to be 12 μM with a signal-to-noise ratio of 3 (S/N = 3).