One-Pot Polyol Syntheses of Ag Right Bipyramids and Nanocubes, and their Surface-Enhanced Raman Scattering Properties

Camphorquinone (CQ)-mediated one-pot polyol methods are developed to synthesize silver right bipyramids and nanocubes. Morphology control between silver right bipyramids and nanocubes is conducted by adjusting FeCl₃ concentration. Silver right bipyramids with an average size of 170 nm and a yield of 87% are obtained with 0.11 mm FeCl₃, while silver nanocubes with an average size of 120 nm and a yield of 70% are obtained with 0.04 mm FeCl₃. The as-synthesized Ag right bipyramids and nanocubes fabricate Surface-enhanced Raman scattering (SERS) substrates with good signal reproducibility to detect the Rhodamine 6G with concentrations down to 10⁻¹²m. The SERS performance of silver right bipyramids larger than 100 nm is experimentally investigated. A comparison of the Raman enhancement effect between Ag right bipyramid and nanocube is conducted by comparing the enhancement factors of as-fabricated Ag right bipyramid and nanocube SERS substrates. The Ag right bipyramid and nanocube SERS substrates are obtained at the same experimental condition, and their enhancement factors are calculated to be 3.11 × 10⁴ and 2.37 × 10⁴, respectively. The fabricated sensitive SERS substrates can potentially be used for ultrasensitive detection of analytes in applications such as food safety and environmental monitoring.