Study of the behavior and determination of phenol Based on modified carbon pa s te electrode with nickel oxide-nitrogen carbon quantum dots using cyclic voltammetry

The behavior of phenol was studied and determined using the modified carbon paste electrode (MCPE) with nickel oxide nanoparticles doped by nitrogen carbon quantum dots as nanoadsorbent (NiO - NCQD) and cyclic voltammetry (CV). The MCP electrode was manufactured in a laboratory. The modified carbon paste consisted of 12% (NiO-NCQD), ­ 44% of graphite powder and 44% of paraffin oil to get a modified carbonate paste. Cyclic voltammetry can provide behavior information; as such: diffusion coefficient (D), charge transfer coefficient (α.nα), the mass transport (mtrans)  found that diffusion coefficient, the reduction of mass transport (mtrans) by increasing the phenol concentration in the solution, and increasing of constant K0 when the concentration of phenol increased in the solution.  Also, the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), and Gibbs free energy (ΔG) are studied and calculated. In this study, EHOMO=4.92eV, ELUMO=0.32eV, and ΔG=-4.17 were considered. The drinking water samples from Latakia city were analyzed based on NiO-NCQD adsorbent using the MCPE method (NiO-NCQD/MCPE). The phenol concentration in the drinking water sample in Latakia was achieved less than the quantitative detection limit (LOQ), and the proposed procedure was validated by spiking samples.