Bio-inspired self-cleaning carbon cloth based on flower-like Ag nanoparticles and leaf-like MOF: A high-performance and reusable substrate for SERS detection of azo dyes in soft drinks

Abstract

Surface-enhanced Raman scattering (SERS) enables azo dye monitoring become rapid and efficient. However, the high cost, low efficiency and poor recyclability of SERS substrate limit its practical application. Herein, we propose a facile strategy to develop self-cleaning carbon cloth as a high-performance and reusable SERS substrate through in-situ growth of leaf-like metal-organic framework (L-MOF) and one-step electro-deposition of flower-like Ag nanoparticles (CC-L-MOF@F-Ag) followed by chemical modification for SERS detection of congo red (CR), chrysoidine (CYD) and acid orange II (AO II) in soft drinks. Taking advantages of superhydrophobicity and SERS-active F-Ag, the prepared self-cleaning CC-L-MOF@F-Ag not only avoids the diffusion-random problem and further boosts sensitivity, but also yields excellent self-cleaning property through facile washing with water, endowing its good reusability and stability. Furthermore, this substrate can realize quantitative detection of CR, CYD and AO II with low limits of detection (0.013 μM for CR, 0.017 μM for CYD and 0.0067 μM for AO II) and wide linear detection range (0.1 – 1000 μM for CR, 0.1 – 1000 μM for CYD and 0.01 – 100 μM for AO II). Meanwhile, CR, CYD and AO II in six soft drinks were also successfully detected with satisfactory recoveries. This method provides a potential and cost-effective strategy to develop advanced SERS sensing device for effective monitoring azo dyes in soft drinks.