Hedgehog Inspired CuO Nanowires/Cu2O Compositesfor Broadband Visible-Light-Driven Recyclable SurfaceEnhanced Raman Scattering

摘要

Self-cleanable surface-enhanced Raman scattering (SERS) spectroscopyaffords a promising route toward environment-friendly biosensors for pointof-care diagnostics. It is of great importance to develop recyclable SERSsubstrates driven by a photocatalytic decomposition process, especially in thevisible range. In this work, inspired by the hedgehog-like structures, a broadbandvisible-light-driven photocatalytic SERS platform with the CuO nanowires(NWs)/Cu2O hetero-nanostructures as the backbone is demonstrated.Via employing the approach of nanosecond laser ablation on Cu sheetcoupled with subsequent thermal oxidation, the formed hedgehog-like, highdensity,and dual-scale microanostructures not only demonstrate enhancedbroadband visible-light-absorption capability even extended to the nearinfrared range but also exhibit boosted interfacial adhesion with favorablestability. Such phenomena imply that the binary oxidized Cu composites decoratedwith metallic nanoparticles can serve as high-performance SERSsubstrates with superior recyclability. Under the visible light illumination, theas-fabricated ternary Ag/CuO NWs/Cu2O composites can be self-cleaned byphotocatalytic degradation of adsorbates, thus leading to recyclable SERSsubstrates, which can preserve more than 85% SERS activity after sevencycles’ measurement. These results pave a new path to realize reusable SERSsubstrates in the applications of remote and resource-limited environmentstoward next-generation green biosensors.