The electrochemical discharges for the synthesis of nickel oxide nanoparticles: Characterization and mechanism

Electrochemical discharges in aqueous solution of sulphuric acid and ethanol as scavenger of hydroxyl radicals, in addition to polyvinylpyrrolidone as stabilizing agent are used for the synthesis of nano-sized nickel oxide colloids. Morphological characterization by electron microscopy and powder X-ray diffraction has been performed to examine the obtained particles at different terminal voltages and experiment durations. From the qualitative resemblance of the electrochemical discharges to the radiolysis technique, a microscopic mechanistic model is proposed giving an overall picture of the physicochemical phenomenon for the synthesis of fine particles.

Graphical abstractNickel oxide nanoparticles successfully manufactured using the electrochemical discharges generated at 30, 36 and 42 V in aqueous solutions of H2SO4 + ethanol + PVP.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Size of nanoparticles depends on the terminal voltage and experiment duration. ► Metal ions are reduced by eaq−, H and species generated by OH scavengers. ► Large particles due to the temperature and pulsatile character of the discharges.