Solvothermal Synthesis of Multiple Shapes of Silver Nanoparticles and Their SERS Properties

The controllable synthesis of nanocrystals with different shapes is very important and challenging. In the present work, silver nanoparticles with different structural architectures, from nanorods, triangular plates, hexagonal plates, and nanocubes to polyhedrons have been synthesized successfully in high yield by a solvothermal process. Especially, the unique silver enneahedral nanoplates are also observed. These nanoparticles exhibit tunable surface plasmon resonance properties from the visible to near-infrared regions. Those nanoparticles were also self-assembled on glass substrates and evaluated as potential surface-enhanced Raman scattering (SERS) substrates using trans-1,2-bis(4-pyridyl)ethylene molecules. Thanks to the enhanced local field effect around their sharp corners and edges, those Ag triangular plates exhibit enhanced SERS properties and can serve as high-sensitivity substrates for SERS-based measurements.