Study of Ag NPs decorated - ZnO nanoflowers for the SERS - Based detection of pesticides: An experimental approach

In the realm of biomedical applications, Surface-Enhanced Raman Spectroscopy (SERS) stands out as a potent analytical technique, offering swift analysis and unparalleled sensitivity. This study diverges from conventional single metallic nanoparticles, spotlighting the efficacy of composite materials, particularly the synergy of ZnO flowers (ZnO) and silver nanoparticles (Ag) in SERS biosensor applications. The resulting Ag NPs - decorated ZnO nanoflowers (ZnO–Ag) structure, acting as a SERS substrate, introduces a profusion of "hot spots" through Ag deposition on 3-D ZnO, facilitated by electron transfer between the noble metal and ZnO, ensuring super-stable SERS activity. Our research presents a cost-effective method for fabricating ZnO–Ag SERS substrates that simultaneously exhibit a high density of "hot spots" and exceptional stability in SERS performance. Investigating the enhancement potential, our investigation focuses on ZnO–Ag with thiram, revealing a meager limit of detection (LOD) at 1.14 × 10⁻¹¹ M and an enhancement factor (EF) of 3.3 × 10⁹. Moreover, considering the number of ZnO layers and optimizing the ZnO surface, an exploration into sensor performance yields compelling results for carbendazim with an LOD of 9.4 × 10⁻¹⁰ M and an EF of 4.9 × 10⁸. This research unveils significant implications, offering a streamlined and remarkably effective solution for the precise detection of pesticide residues in the environment.