A novel strategy for improving SERS activity by cerium ion f → d transitions for rapid detection of endocrine disruptor

Abstract

• The special electron motion of Ln doped semiconductors is creatively applied to the field of SERS. • A quick Ce 4+ ↔ Ce 3+ reaction increase the fast electron transfer and enhance the SERS intensity. • Fast and ultra-sensitive detection of BPA within one minute. • BPA detection limit as low as 0.0001 ppm is the lowest among all reported semiconductor substrates. Semiconductor doping offers a wide range of applications in fields from catalysis to electronics. However, for Surface-enhanced Raman spectroscopy (SERS), not many studies are conducted for the commercialisation of this technology. A simple method was developed to synthesise ultra-stable, repeatable, uniform Ce-doped ZnO (Zn 1−x Ce x O) with a high SERS activity. The SERS signals of 4-MPy collected on Zn 1−x Ce x O exhibited 118 times higher enhancement than those of ZnO. Cerium ion f → d transitions dominated Charge transfer (CT) is the main cause for this enhancement. The prepared Zn 1−x Ce x O nanoparticles (NPs) can be used to detect Bisphenol A (BPA) with a detection limit of 0.0001 ppm. To our best knowledge, this is the optimum performance reported for semiconductor substrates. Our work paves a way towards highly sensitivity, great-uniformity, high-stability, fast-detection and cost-effective SERS substrates, which can be a promising tool in high-sensitivity contaminant monitoring.