Fabrication of Au nanoparticles embedded holey g-C3N4 as SERS substrates for sensitive and reliable detection

Abstract

Holey g-C3N4 (H-C3N4) with in situ grown Au nanoparticles (Au@H-C3N4) was synthesized to produce high performance and ultrasensitive SERS active substrates. The H-C3N4 with the porous structure provided the support for embedding enough Au NPs, which avoided the aggregation of Au NPs on the surface of H-C3N4. The results showed that crystal violet as a Raman probe showed a detection level of 2.7 × 10−9 M with an enhancement factor of 6.8 × 105. Au@H-C3N4 was used successfully to detect the residues of prohibited additives, melamine and sodium thiocyanate, from milk samples, which displayed a good linear range from 1 × 10−4 to 5 × 10−7 M (R2 = 0.986) and 1 × 10−3 to 5 × 10−6 M (R2 = 0.971), respectively. In this study, Au@H-C3N4 SERS substrates with high sensitivity have high potential as SERS platform for trace detection.