Highly sensitive, reproducible and uniform SERS substrates with a high density of three-dimensionally distributed hotspots: gyroid-structured Au periodic metallic materials

Inspired by butterfly wings, a team in China has developed by a technique that enables nanotextured gold surfaces to be reproducibly made. Metal nanostructures can enhance the interaction between light and matter, making them useful for the sensitive optical detection of molecules in a technique called surface-enhanced Raman spectroscopy (SERS). But practical application of this concept requires substrates that can be and behave uniformly across their surfaces. Now, Wang Zhang from Shanghai Jiao Tong University and co-workers has fabricated a SERS substrate using a template based on the wing scales of the green hairstreak butterfly. Its surface consists of an array of three-dimensional gyroid structures. The substrates, which were reproducible, uniform and highly sensitive — enhancing the detection signal by up to a factor of one billion — are promising for highly sensitive molecular detection.