Effect of crystallographic defects on metallic nanoparticles stability from the standard free energy perspective

Compared to bulk metals, metallic nanoparticles are much more unstable and susceptible to oxidation. Although this instability is often attributed to the increased surface energy resulting from a larger surface area, defects may further degrade the stability. The instability of defect-introduced metallic nanoparticles is quantitatively evaluated by electrochemical measurements in this study. These nanoparticles exhibit lower electrode potentials compared to pure metal plates, and the degree of instability caused by defect introduction can be quantified from a Gibbs free energy perspective. Furthermore, we discuss the redox rates based on polarization curves to correlate instability with the actual dissolution (oxidation) behavior.