Synthesis Of Ag Nanoparticles By Phytochemical Method And Its Application On Electrochemical Sensor For The Detection Of Nitrite Ions

A novel electro-chemical sensor for the detection of(NO2-)was fabricated by silver nano-particles(Ag-NPs)which were prepared through phytochemical method.The Ag-NPs were prepared by using the aqueous extract of Dimocarpus longan seeds as the stabilizing and reducing agent.Nano particle are generally cluster of atoms are in the different size range.It is known that the property of metal NPs has been characterized by the state of the art physicochemical techniques,the formation,and growth of Ag-NPs were determined by UV/vis,the face-centered cubic structure of Ag-NPs,confirmed by X-Rays Diffraction method.The surface morphology has been determined by using scanning electron microscope(SEIM)that completely elaborates its formation.Beside this the size and microstructure of the synthesized particles was measured by transmission-electron-microscopy(TEM)and the average particle size was found to be in the range of 2-20 nm.Furthermore,the electrochemical behavior of silver nanoparticles was systematically evaluated.Direct electrochemistry analysis of the synthesized Silver nanoparticles confirmed that the NPs retained their direct electrochemical activity.The prepared Ag-NPs were mixed with graphite powder to make an electrode by dipping technique.The fabricated electrode displayed enhanced electrochemical performance for nitrite ions oxidation.The modified electrodes display incredible electrochemical performance giving higher peak current density and lower oxidation over potential than those found for the bare electrode and modified GSE electrode.In comparison to other techniques,the electrochemical methods have become further delightful due to its ease of availability,high sensitivity and selectivity.For the electrochemical behaviors of the fabricated electrode exposed strong oxidation peak at 0.85 V.A good linear relationship was found between the current responses and concentration of nitrite(0.05 mmolL-1to 10 mmolL-1),while the detection limit was calculated as 0.01 mmol L-1.The Ag-NPs modified electrodes were applied in the simulated water sample.The results showed that the coexisted ions have little effect on the detection of nitrite except for the reducible ions(such as Fe2+).The RSD of parallel measurements to detect nitrite using the modified electrode was less than 5%and the sensitivity lose about 8.2%for a week.It is concluded that the electrode modified by Ag-NPs has the potential for environmental pollution remediation.