Comparison of two different nickel oxide films for electrochemical reduction of imidacloprid

Abstract

A nickel oxide (NiO) thin film was successfully prepared on Ni foil via a sol-gel method and a reduced state nickel oxide (r-NiO) thin film was obtained by etching NiO with hydrazine hydrate solution. Structure characterization through X-ray diffraction and scanning electron microscopy revealed the growth of nanostructure films on the surface of nickel foil. Cyclic voltammetry, linear sweep voltammetry and electrochemical impedance spectroscopy were used to assess the performance of the two films.Electroreduction of alkaline imidacloprid solution under potentiostatic conditions was carried out in a three-electrode system. The removal efficiencies of 80.2% (r-NiO) and 66.3% (NiO), and the current efficiencies of 67.3% (r-NiO) and 58.9% (NiO) were much higher than 41.7% (removal efficiency) and 0.003% (current efficiency) on the bare Ni electrode. This study prepared two novel thin films with composites of NiO or r-NiO, and thus provided feasible and efficient electrochemical degradation of imidacloprid. The degradation products were characterized and the possible degradation pathways were proposed.

A Review on Methods for the Elimination of Imidacloprid: 2018–2022

“…The high removal potential of r‐NiO is attributed towards its resistance in charge transfer and its electrocatalytic activity. The electrochemical degradation mechanism of imidacloprid was estimated via three pathways i) the charge transfer at the electrodes results in the formation of alkene imidacloprid due to H‐atom elimination which is further degraded into 6‐chloronicotinic acid ii) hydrolysis of imidacloprid leads to the formation of principal product i. e., imidacloprid urea and iii) the loss of −NO 2 leads to the formation of imidacloprid guanidine [87] …”

“…The electrochemical degradation mechanism of imidacloprid was estimated via three pathways i) the charge transfer at the electrodes results in the formation of alkene imidacloprid due to H-atom elimination which is further degraded into 6chloronicotinic acid ii) hydrolysis of imidacloprid leads to the formation of principal product i. e., imidacloprid urea and iii) the loss of À NO 2 leads to the formation of imidacloprid guanidine. [87] A comparative study of the removal of imidacloprid using Fenton like catalysts viz natural iron minerals and zero-valent metals was investigated in 2021 by Liu et al The author employed ilmenite, pyrite, zero-valent iron (ZVI), vanadium titano-magnetite (VTM), and zero-valent copper (ZVC) for carrying out the analysis. Various catalysts were reported to show different behaviour viz i) ZVI exhibited the highest removal rate of 96.8 % using 10.78 mmol/L H 2 O 2 at pH 3 ii) VTM showed efficient activity but possess low reusability iii) pyrite was reported to possess medium removal ability toward imidacloprid even after various cycles (10.5 % in the 5 th use).…”

Plasmon Chemistry on Ag Nanostars: Experimental and Theoretical Raman/SERS Study of the Pesticide Thiacloprid Bond Cleavage by the Plasmon Deactivation Effect

“…Currently, there are two general strategies to reduce or degrade this type of compound: (i) reduction of pesticide levels in the environment through membrane filtration, , surface adsorption, , or biological degradation , and (ii) degradation of pesticides by chemical methods such as electrochemical, − organic photocatalysis, radicals such as oxidizing agents, photochemical, and photolysis, − among others. However, all these methods can potentially generate chemical species that could be more toxic than the initial precursor.…”

Efficient removal of Imidacloprid and nutrients by microalgae‐bacteria consortium in municipal wastewater: effects, mechanism, and importance of light

“…20,21 Chemical degradation of IMI mainly includes photocatalytic degradation, 22 advanced oxidative degradation, 23,24 and electrochemical degradation. 25,26 Biodegradation of IMI mainly focuses on the degradation and transformation of microorganisms in environments, such as the removal of IMI by bacteria and algae in soil and water bodies. [27][28][29] At present, most of the research on removing pesticides and other emerging pollutants by microalgae was carried in the culture medium environment and the synthetic wastewater environment, mainly focusing on the degradation pathway and mechanism.…”

“…Now many researches show that IMI can be recovered by physical methods, such as filtration and adsorption; however, the undegraded IMI may still harm the environment and its organisms 20,21 . Chemical degradation of IMI mainly includes photocatalytic degradation, 22 advanced oxidative degradation, 23,24 and electrochemical degradation 25,26 . Biodegradation of IMI mainly focuses on the degradation and transformation of microorganisms in environments, such as the removal of IMI by bacteria and algae in soil and water bodies 27‐29 …”