Nanostructured Surface-enhanced Raman Scattering Research Articles

CVD graphene-based flexible and transparent SERS substrate towards L-tyrosine detection

The simple, rapid, reproducible, and sensitive detection of trace amounts of molecules is of great interest in terms of early diagnosis of diseases and food safety in daily-life applications. In this study, low-pressure chemical vapor deposited (LP-CVD) graphene(G)-based flexible and transparent AgNPs/CVDG@AryLite™ nanostructured surface enhanced Raman scattering (SERS) substrate has been demonstrated towards the detection of L-Tyrosine (L-Tyr) amino acid molecules. The synthesize of high-quality, single-crystal monolayer graphene films was achieved with considerably low (62.81 Ω sq.−1) sheet resistance and 94% transmittance at 550 nm wavelength. AgNPs are uniformly formed with a size distribution of about 60 nm on the CVDG surface. The fabricated substrates have been investigated by Rhodamine 6G (R6G) as probe molecule and L-Tyr amino acid molecules with different concentrations to understand the SERS properties. Significant enhancement of R6G and L-Tyr on the fabricated AgNPs/CVDG@AryLite™ SERS substrates obtained even if the 10−8 M R6G and L-Tyr solutions are used. The enhancement factors (EFs) are calculated as 109 and 7.5 × 109 for R6G and L-Tyr, respectively. The results in this research show that the fabricated nanostructured SERS substrates might open up a new path to design flexible and transparent optoelectronic devices towards detection of trace amount of molecules particularly portable spectroscopic instruments.