Synthesis and Characterization of Carbon Nanoporous Matrix Enriched with Nickel Oxide and Silica Nanoparticles for Glucose Sensor Applications

Abstract

Abstract: Nickel oxide (NiO) and silica (SiO₂) nanoparticles were incorporated into a carbon nanoporous matrix based on a pyrogallol-formaldehyde (PF) matrix via the sol-gel method. Various characterization techniques were performed to investigate the PF matrix, PF:NiO and PF/SiO₂:NiO nanocomposites. XRD patterns revealed broad peaks characteristic of amorphous SiO₂ and carbon phases characteristic of both amorphous SiO₂ and carbon phases along with three characteristic nickel (Ni) peaks in the two nanocomposites PF:NiO and PF/SiO₂:NiO. SEM images showed a significant number of particles covering the PF matrix surface in the PF/SiO₂:NiO nanocomposite. The TEM images confirmed the porous structure of the PF matrix, a uniform dispersion of Ni nanoparticles in the PF:NiO nanocomposite and notable nanoparticle agglomeration in the PF/SiO₂:NiO nanocomposite. Electrochemical measurements demonstrated that the sensitivity of the non-enzymatic glucose sensor increases with decreasing specific surface area. The electrical conductivity of the materials was found to depend on pore volume, decreasing as pore volume increased. The PF/SiO₂:NiO nanocomposite exhibited promising performance as a non-enzymatic glucose sensor with a sensitivity of 585 µA·mM⁻¹·cm⁻² and a low electrical conductivity of approximately 10⁻⁸ Ω⁻¹·cm⁻¹.

Keywords: Carbon nanoporous matrix, Nanocomposites, Nickel oxide, Silica, Non-enzymatic glucose sensor, Electrical conductivity.