Hierarchical MoS2-microspheres decorated with 3D AuNPs arrays for high-efficiency SERS sensing

Three-dimensional (3D) distribution Au-nanoparticles (AuNPs) arrays have enabled surface-enhanced Raman scattering (SERS) for a variety of analytical applications due to the spatial-distribution plasmon. Herein, we present a new route for synthesis of 3D SERS powder, hierarchical MoS2-microspheres (MoS2-MS) decorated with “cauliflower-like” AuNPs arrays (CF-AuNPs), for high-efficiency molecular detection. Finite element simulations have shown that the spatial-distribution nanogaps can generate intensive SERS hot spots. Using the CF-AuNPs@MoS2-MS for in-situ molecular detection, not only have 10−14 M rhodamine 6G or methylene blue been identified with different laser wavelength excitation (532 and 633 nm), but also various metabolites in human early-morning urine were recognized. Moreover, the wafer-scale flexible SERS substrates consisted of CF-AuNPs@MoS2-MS inset cellulose acetate membrane (CAM) were fabricated via suction filtration method, showing good SERS sensitivity for adenosine detection.