Unexpected solution phase formation of hollow PtSn alloy nanoparticles from Sn deposition on Pt dendritic structures

Hollow nanoparticles with a high surface-to-volume ratio have found various applications in catalysis, sensors, and energy storage, and thus new synthetic routes to these structures are of great interest. One of the best-known synthetic routes to hollow nanostructures is the utilization of the Kirkendall effect, which, however, is not useful for systems with a slow diffusing-out core such as Pt and fast diffusing-in surface elements such as Sn. Herein, we report a counterintuitive formation of hollow PtSn nanostructures by reacting dendritic Pt nanostructures with Sn precursors.