Bi-functional Au/FeS (Au/Co3O4) composite for in situ SERS monitoring and degradation of organic pollutants

Abstract The bi-functional Au/FeS (Au/Co 3 O 4 ) composite was fabricated by in situ reducing Au nanoparticles onto the surface of FeS (Co 3 O 4 ). The as-prepared FeS possessed a multi-structure composed of plenty of nanoplates, which were coated by Au nanoparticles with an average size of ~47.5 nm. While the Co 3 O 4 showed a thin hexagonal sheet containing Au nanoparticles on its surface with an average size of ~79.0 nm. Both the as-prepared Au/FeS and Au/Co 3 O 4 composites exhibited excellent SERS performance, capable of enhancing the Raman signals of R6G molecules with the enhancement factor up to 1.81 × 10 6 and 7.60 × 10 4 , respectively. Moreover, Au/FeS (Au/Co 3 O 4 ) composite also has been verified to have intrinsic peroxidase-like activity, which could decompose H 2 O 2 into hydroxyl radicals and then degrade organic pollutants into small molecules. Therefore, SERS can be used to real-time and in situ monitoring the degradation process of R6G molecules, employing the Au/FeS (Au/Co 3 O 4 ) composite both as SERS substrate and catalyst. Graphical abstract SERS was used to real-time and in situ monitoring the degradation of R6G, employing the Au/FeS and Au/Co 3 O 4 composites both as SERS substrates and catalysts.