Why are Silver Nanoparticles More Toxic Than Bulk Silver? Towards Understanding the Dissolution and Toxicity of Silver Nanoparticles

作者：Batchelor McAuley Christopher^*; Tschulik Kristina; Neumann Christopher C M; Laborda Eduardo; Compton Richard G

来源：International Journal of Electrochemical Science, 2014, 9(3): 1132-1138.

DOI：10.1016/s1452-3981(23)07783-0

• Silver nanoparticles
• redox dissolution
• oxygen reduction
• toxicity
• mass-transport

The mass-transport to a spherical particle in solution is considered in the context of the mechanism of oxygen reduction on silver nanoparticles. For small particles (%26lt;= 1 mu m) the reduction follows a two-proton, two-electron pathway due to the rapid diffusion of the intermediate hydrogen peroxide away from the interface. Above this size threshold the hydrogen peroxide is further reduced to water. This switch of mechanism is of importance when interpreting the dissolution of silver nanoparticles in aqueous media and their inherent toxicity. The release of H2O2 from nanoparticles but not bulk silver may explain why silver nanoparticles are thought more toxic than their macroscopic counterparts.

• 出版日期2014-3