Electrochemical synthesis of tin plasmonic dendritic nanostructures with SEF capability through in situ replacement

Dendrite nanostructures with noble metals, such as Au and silver, act as plasmonic substrates with excellent potential in enhanced fluorescence technology. However, tin dendritic nanostructures are poorly investigated. In this study, we proposed a method of in situ electrochemical synthesis replacement to fabricate highly branched tin dendritic nanostructures on aluminum substrates. The surface enhanced fluorescence performance of the tin dendrites was tested for the detection of rhodamine 6G as probe molecules, and the result showed that the enhancement factors can reach to 36.5-fold that of an aluminum substrate. The fabricated tin dendrites have numerous nanogaps between the stratified and adjacent ones, thereby creating many plasmon-active "hotspots" dedicated to enhanced fluorescence. Electrical field simulation results for the tin dendritic nanostructures proved that its nanogaps can enhance the nearby local electromagnetic field. As a result, tin dendritic nanostructures exhibit outstanding surface enhanced fluorescence and promising application in biomolecule detection and sensor devices.