Electrochemical detection of herbicide atrazine using porous MnO2-NiO nanocatalyst

Herein, I report a simple and novel method to the synthesis of MnO2 nanotube decorated with NiO nanoparticles via a simple hydrothermal process, accompanied by a calcination step. The prepared MnO2-NiO nanocomposite was then studied as electrochemical sensing material for the detection of atrazine. I achieved a detection limit of 400 × 10−9 M; the linear range for atrazine was from 0.8 × 10−6 to 120 × 10−6 M in pulse amperometric mode. Moreover, MnO2-NiO modified electrode showed good anti-interference property. In the electrochemical impedance spectroscopic investigation, MnO2-NiO modified electrode exhibited a decrease in the electron transfer resistance in response to increase in the concentration of atrazine indicating improved electron-transfer kinetics for atrazine reduction. Zeta potential study and electrochemical studies further proved that atrazine molecule adsorb onto the MnO2-NiO. The applicability of MnO2-NiO modified electrode was also demonstrated in tap and waste water samples, showing the feasibility of its use for electrochemical sensing application.