Maros Halama

Abstract:

Corrosion properties of Ag and Au nanoparticles in water-based environment were compared using electrochemical techniques hyphenated with quartz-crystal microbalance. In addition, quantum chemical calculations of Ag nanoparticles and Ag nanoparticles/ascorbic acid hybrid system were performed to find out how theoretical approach can contribute as support for laboratory experiments. An assessment of dissolution rate from measured corrosion parameters for both bare and inhibited nanoparticles was determined in Hank solution as simulated human body fluid. The dramatic change of redox behaviour for Ag nanoparticles was observed in the presence of antioxidant molecules of ascorbic acid (AsA). Inhibition effect in dissolution of Ag NPs initiated by AsA was theoretically proofed by performing quantum chemical calculations of redox properties of studied hybrid system. The quantum-chemical calculation has showed that the electrons are mainly transferred from AsA molecule to nanoparticle and the free radicals are suppressed. Combination of these techniques help to study unknown thermodynamics, corrosion of nanoobjects and finally assessment of the life-time of NPs applied in environment of interest.
What will audience learn from your presentation?
• The aim is to highlight problem related with opening “Pandora´s box” regarding reactivity of NPs and their interaction with environment due to the changes of redox properties by surface modification.
• Prediction of life-time of metallic nanobjects in application environment by monitoring of corrosion phenomena.