Fabrication of Au-Decorated Al Nanoconcavities Platform for Augmented SERS

A robust and competitive technology to synthesize arranged high-density gold nanoparticles on highly uniform Al nanoconcavities substrates is presented. The nanoparticles are formed through sputtering and thermal annealing treatment on Al templates, which are synthesized through particular removal of nanoporous anodic alumina structure with controlled anodization conditions and with phosphoric acid as electrolyte. This scalable fabrication mechanism regulates the particle size, arrangement, shape and interparticle separation across large surface areas, which empowers the optimization of their surface enhanced Raman scattering (SERS) activities. 4-mercaptopyridine is selected as a probe molecule. Analysis reveals that Au-decorated Al nanoconcavities substrates are highly competitive for the enhancement of Raman signals and could be employed as self-sustaining nanosensors. By using these templates, a concentration as low as 10-7 M of 4-mercaptopyridine is easily detected. Finally, the calculated EF factor of 1.1 x 107 confirms the suitability for effective and sensitive SERS detection of the developed substrates. High-density gold nanoparticles arranged on self-ordered Al nanoconcavities are presented as a robust and competitive platform for surface enhanced Raman scattering (SERS) applications. Gold nanoparticles are formed by sputtering and a thermal annealing treatment on Al nanoconcavities templates. High spatial resolution and tunable plasmonic bands with a high magnification SERS signal can be obtained.image

Automated summary

A robust and competitive technology for synthesizing arranged high-density gold nanoparticles on highly uniform Al nanoconcavities substrates is introduced. The formation of nanoparticles is achieved through sputtering and thermal annealing treatment on Al templates, which are obtained by removing nanoporous anodic alumina structure selectively with controlled anodization conditions and phosphoric acid as electrolyte. The resulting substrates exhibit high performance for surface enhanced Raman scattering (SERS) detection and can be used as self-sustaining nanosensors, with a low detection limit of 10-7 M for 4-mercaptopyridine and a calculated EF factor of 1.1 x 107.