Recyclable SERS monitoring of food quality based on the shrubby morphology of titania oxide-triggered electromagnetic “hotspots”

Abstract

Constructing of plasmonic substrate with the capability of detecting nutritional food quality will soon be emerged as the frontier research directions with broad prospects in surface-enhanced Raman scattering (SERS) technology ascribed to an improvement of living standards. Herein, a novel TiO2 framework with a shrubby morphology was successfully constructed on carbon cloth (CC) matrix to trigger significantly enhanced electromagnetic “hotspots” after dense Ag network with numerous sharp corners and edges was formed by a photo-induced reduction. Particularly, the structure-dependent optical performance was investigated for these as-prepared CC/TiO2/Ag hybrid substrates, screening out an optimal one with an enhancement factor of 6.38 × 107. Regarding a prominent photocatalytic efficiency ascribed to the high electron-hole separation efficiency assisted by the CC matrix and Ag decoration, a recyclable SERS-based monitoring of quercetin (QR) was achieved in teas, demonstrating recovery values distributed from 88.9 % to 106.4 %. The strategy proposed here opened a new way to create high-density “hotspots” for multifunctional SERS substrates, which might play a crucial role in food quality monitoring applications.