Reliable and reusable plasmonic substrates are crucial for the development of biosensing applications using surface-enhanced Raman scattering (SERS), as they can provide unique advantages for ultrafast and accurate single-molecule recognition of different species. These properties are unrevealed in this paper, where thermally annealed cupric CuO and cuprous oxide Cu2O heterostructures were used as templates for highly stable nanotextured surfaces and design of robust 3D plasmonic biochips. Differently tailored nano/micro-roughness provided outstanding light trapping abilities that lead to significant SERS performance improvement. It was found that Cu2O chestnut-like substrate activated with 80 nm Au/Pd alloy film reveals impressive 3.7-fold Raman signal increment in respect to grainy-like structure and about twice larger amplification than that of nanowires enriched platform decorated in the same manner. Large enhancement factor AEF ~5 × 105 of a chestnut-like Au/Pd@/Cu2O chip allows adding it up to the list of the most effective oxide-based plasmonic substrates. Moreover, the substrate shows unprecedented durability during repetitive plasma-cleaning, demonstrating a remarkable 100% self-recovery in less than 1 min, accompanied by virtually no thickness degradation of the plasmonic layer.
- Bimetallic plasmonic activation
- Low reflectance copper oxide heterostructures
- Reactive plasma cleaning