Synthesis of silver nanoparticles in the presence of polyethylene glycol and their electrochemical behavior at a graphite electrode by cyclic voltammetry

The shape, size, optical properties and electrochemical activity of the silver nanoparticles (AgNPs) were studied, as well as their dependence on the amount of the reducing agent, the method of initiation of the formation of nanoparticles and the introduction order of reagents in the reaction mixture. It was determined that in the sols obtained without polyethylene glycol (PEG) AgNPs are predominant with the average size of 40 nm. With PEG the triangular AgNps predominate with the average size of 20 nm due to the silver ions reduction on the surface of the nuclei. It was determined that AgNPs are most active when obtained with PEG and the molar ratio [Ag]:[C₆H₅O7^3-] = 1:5. On the anodic branch of the cyclic AgNPs curve the splitting of anodic maximum into two due to AgNPs oxidation was observed.AgNPs obtained in the presence of PEG by light have the most electrochemical activity.The processes of AgNPs oxidation become easier when PEG is present which is caused by the formation of the most stable silver oxides.