Semiconductor Enhanced rGO/Ag⁰/ZnO Ternary Hybrid Revealing Charge Transfer Enhancement in SERS Detection of Raman Reporter Molecules

Abstract

In this work, we have investigated the role of the chemical enhancement mechanism in SERS detection on a ternary hybrid substrate fabricated by incorporating ZnO nanostructures into an in situ synthesized reduced graphene oxide/silver composite. The sensing performance of the ternary substrate at various ZnO concentrations is investigated using Raman reporter molecules (RRM) such as Rhodamine 6G and 4‐Mercaptobenzoic acid. The SERS signals show enhancement by adding varied amounts of ZnO, revealing a new way of SERS enhancement by incorporating semiconductor nanostructures rather than conventional hotspot engineering. To probe chemical enhancement, we kept the electromagnetic contribution constant by keeping the same concentration of Ag in all the substrates investigated in this study. The obtained enhanced SERS signals of the probe molecules reveal the contribution from the chemical enhancement mechanism with the addition of ZnO. This vital observation reveals a new gateway in the field of SERS detection for developing a semiconductor‐enhanced, economical, and sustainable SERS substrate.