Figure 2.

Effects of (A) R6G concentration, (B) reaction times, and (C) pH on the SERS signal of R6G at 1361 cm⁻¹ when using Ag₂Te NPs as a substrate. The concentrations of Ag₂Te NPs were both 0.001 × in (A) and (B), of Hg²⁺ were 0 in (A) and 100 nM in (B) and (C), and of R6G were both 10 μM in (B) and (C). The pH values were both 4.0 in (A) and (B) and reaction times were both 10 min in (A) and (C). I_R0 and I_R are the SERS intensities of R6G at 1361 cm⁻¹ in the absence and presence of Hg²⁺ (100 nM), respectively, in (B) and (C).