One-Step Method for the Direct Growth of NiO Nanoflowers on Pencil Graphite Electrode for Highly Sensitive Non-Enzymatic Glucose Sensing

Electrochemical glucose sensors, including enzymatic and non-enzymatic sensors, have been considered as quick, accurate, and efficent means for glucose measurement. Recently, non-enzymatic electrochemical glucose sensor based on metal oxides have been paid attention to develop thank to their outstanding behaviours. In most of these studies, metal oxides were synthesized individually and subsequently deposited on the electrode surface using a binder. In this study, we aim at developing a non-enzymatic glucose sensor based on NiO nanoflowers directly grown on a commercial pencil graphite electrode. NiO matetials were deposited on the electrode without a binder via a facile and low-cost chemical procedure. The synthesised materials' morphologies and components of were characterized by a field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction analyses. Electrocatalytic performance was recorded by cyclic voltammetry and chronoamperometry. The resulting NiO nanoflowers, characterized by funnel-shaped structures measuring 500-600 nm in diameter and 20 nm in thickness, were formed on the pencil graphite electrode. The fabricated electrode showed a remarkably high sensitivity of 337 mu A mM-1 cm-2, a low limit of detection of 4 mu M, and good selectivity. The fabricated electrode can be a potential candidate for clinically medical applications.