Modified carbon paste electrode based on nanotechnology for determining phenol in the liquid solutions by cyclic voltammetry and comparing to high-performance liquid Chromatography

In this paper, phenol was determined in a liquid solution based on fabricating a phenol-selective electrode by cyclic voltammetry (CV). The carbon pa s te electrode was modified with nickel oxide nanoparticles (NiO) which were doped with nitrogen carbon quantum dots (NCQD) as the NiO-NCQD nanocomposite. The modified carbon pa s te electrode was manufactured in a laboratory and the effect of pH was s tudied. In the optimized condition, the be s t results were created at pH 7.0 and 4.0 using KH2PO4 buffer solution. By voltammetry, the voltage was optimized, and the be s t value for the voltages was obtained at 0.04166V and 0.05991V for pH 4 and 7, respectively. The scan rate (SR) was s tudied and the be s t SR was achieved at 100 mv s-1 for both pH. Due to the results, a wide linear dynamic range between 10 to 1000 μM was obtained. Also, the s tandard phenol solution was analyzed by high-performance liquid chromatography (HPLC). The retention time (RT), the wavelength maximum (λ max: nm), and the peak area equation of HPLC were achieved at 2.982 min, 270 nm, and (Area=40420CPhenol+ 43.557), respectively by the concentration range of 0.1-5.0 mg L-1. The modified carbon pa s te electrode with NiO-NCQD was used for determining phenol by cyclic voltammetry and compared with the HPLC technique. The results showed that there was no significant difference between the two methods.