Facile synthesis of noble metal decorated carbon nanostructure for SERS detection

Abstract

Surface enhanced Raman scattering (SERS) is a highly sensitive spectral analysis technique for ultra‐low trace molecule detection. Conventionally, noble metals like silver (Ag) and gold (Au) are used to prepare the SERS substrates; however, it usually requires careful experiment design and accurate process control, which defers their wide applications in practice. In this paper, a one‐step and low‐cost approach to prepare silver decorated porous carbon (Ag NPs/PCN) films for SERS application is reported. Experimentally, gelatin‐silver nitrate mixed solution was first spin‐coated on the Si substrates to form the thin films, and then, the substrates were carbonized at the different temperatures to obtain the Ag NPs/PCN films. The SERS performance of the Ag NPs/PCN films was evaluated by using the R6G as Raman reporter. Results reveal that the SERS activity is closely related to the spin‐coating rate and carbonization temperature. And detection limit of 10−8 M with the Raman enhancement factor of 1.64 × 106 (10−4‐M R6G) can be obtained on the most optimal substrate. Moreover, large‐scale mapping measurement further evidences that excellent Raman signal uniformity with the RSD of 6.93% also can be achieved.

Plasmonic metasurface assisted by thermally imprinted polymer nano‐well array for surface enhanced Raman scattering

“…Here we observe close to 200% enhanced SERS signal for the nanotrench network of 13 nm film thickness relative to the nanoisland structure at 7 nm. Using an extrapolated value for a concentration of 100 µM on a reference substrate of pure silicon wafer (Figure S3a,b), an overall enhancement factor was calculated to EF ≈ 0.1×10 6 for the metasurface, a highly meritorious value for SERS comparing to other reports, [ 49–51 ] considering the robustness of the surface and the simplicity of the preparation method.…”

Are morphologies of SERS active substrates multifractals? An in‐depth study from multifractal detrended fluctuation analysis

“…[6][7][8][9][10][11][12][13][14] Although understanding the influence of near-field plasmonic architectures of the substrates on the far-field SERS spectra has been a matter of explicit concern these days, [8,15,16] the other avenue in this area of research is deeply focused on the fabrication of highly efficient and reproducible SERS active substrates. [10,[17][18][19][20][21][22] Successful fabrications of such substrates in a way will allow not only to use them as reliable "labon-chip" for diagnostic applications but also may help to contemplate closely on the mechanism behind the SERS phenomena.…”