Highly Durable and\nReusable 3D Copper Foam-Based SERS\nSubstrate with CuO-Ag Nanorods for Ultrasensitive Measurements of\nRhodamine-6G and Human Urine

A three-dimensional structure has\ngarnered significant\ninterest\nas a potential material for ultradurable and recyclable surface-enhanced\nRaman scattering (SERS). Leveraging the superior chemical and physical\nstability, together with the extensive surface area of the 3D copper\nfoam (CF), CuO nanorods were grown within the CF to increase the surface-active\narea and photocatalytic properties. CF@CuO-Ag was effectively fabricated\nto boost the SERS performance through the deposition of Ag nanostructures\nonto the surfaces of CuO nanorods. The CF@CuO-Ag substrate exhibited\nexceptional sensitivity, detecting Rhodamine-6G (R6G) at concentrations\nas low as 10 ρM and successfully analyzing actual human urine\nsamples. The substrate demonstrated remarkable recyclability, maintaining\nSERS efficiency after three cycles of UV cleaning for both R6G and\nurine samples. Furthermore, it has shown exceptional physical stability,\nenduring abrasion from sandpaper, and preserved surface integrity\nafter 25 days of exposure to air. The remarkable sensitivity and stability\nof the CF@CuO-Ag substrate render it a promising choice for the rapid\non-site detection of fungicides and antibiotics in soil and future\ndisease monitoring.