Synthesis and surface enhanced Raman scattering performance of Ag dendritic nanoplates with ultrasmall nanogaps

Ag dendritic nanoplates were synthesized by a facile reduction method with the assistant of trisodium citrate and hydrogen peroxide. The nanoplates exhibited large smooth surfaces full of ultra-small gaps with the diameters of 2-20 nm. The as-synthesized dendritic nanoplates showed significant surface-enhanced Raman scattering (SERS) activity with an enhancement factors of 6.0 × 105, attributing to the enhanced local electromagnetic field around these nanogaps on the surfaces. Particularly, a detection limitation of 1 × 10−9 M for 4-mercaptobenzoic acid was obtained. Other excellent properties such as good homogeneity and reproducibility were also achieved in the Ag dendritic nanoplates with relative standard derivation values of about 8% for different test dots on just one sample and 10% for different pitches of samples.