Polyaniline-Supported Nickel Oxide Flower for Efficient Nitrite Electrochemical Detection in Water

Abstract

A modified electrode with conducting polymer (Polyaniline) and NiO nanoflowers was prepared to detect nitrite ions in drinking water. A simple method was used to prepare the NiO nanoflower (NiOnF). Several techniques characterized the as-prepared NiOnF to determine the chemical structure and surface morphology of the NiO, such as XRD, XPS, FT-IR, and TGA. The activity of the electrode toward nitrite sensing was investigated over a wide range of pH (i.e., 2 to 10). The amperometry method was used to determine the linear detection range and limit. Accordingly, the modified electrode GC/PANI/NiOnf showed a linear range of detection at 0.1–1 µM and 1–500 µM. At the same time, the limit of detection (LOD) was 9.7 and 64 nM for low and high concentrations, respectively. Furthermore, the kinetic characteristics of nitrite, such as diffusion and transport coefficients, were investigated in various media. Moreover, the charge transfer resistance was utilized for nitrite electrooxidation in different pH values by the electrochemical impedance technique (EIS). The anti-interfering criteria of the modified surfaces were utilized in the existence of many interfering cations in water (e.g., K+, Na+, Cu2+, Zn2+, Ba2+, Ca2+, Cr2+, Cd2+, Pd2+). A real sample of the Nile River was spiked with nitrite to study the activity of the electrode in a real case sample (response time ~4 s). The interaction between nitrite ions and NiO{100} surface was studied using DFT calculations as a function of adsorption energy.

Construction of chitosan-supported nickel cobaltite composite for efficient electrochemical capacitor and water-splitting applications

“…The thickness of the NiOOH layer increases in direct proportion to the number of potential sweeps. The presence of OH - ions can be ascribed to, in accordance with the subsequent equation 55 – 57 : …”

High-performance spinel NiMn2O4 supported carbon felt for effective electrochemical conversion of ethylene glycol and hydrogen evolution applications

“…According to the oxidation mechanism of ethylene glycol compounds on Ni-based catalysts, NiOOH plays a catalytic function, and the oxidation steps takes place after Ni(OH) 2 is converted to NiOOH 56 , 57 .…”

Chitosan Supports Boosting NiCo2O4 for Catalyzed Urea Electrochemical Removal Application

“…The confirmation of reversibility can be established through the positive shift of the Ep with an increase in the scan rate. The Laviron Equation (6) for irreversible reactions was utilized to observe a change in the location of the peak potential through an increase in the scan rate values [ 62 , 63 ]: …”