Laser-MBE of nickel nanowires using AAO template: a new active substrate of surface enhanced Raman scattering

The highly ordered anodic aluminum oxide (AAO) template was fabricated using aluminum anodizing in electrolytes with two-step method, which apertures were about 50-80nm. The nickel nanowires with about 40-70nm in diameter was prepared on the AAO template by laser-MBE (molecular beam epitaxy). And high quality Raman spectra of SudanII were obtained on the glass covered with the nickel nanowires. On the nickel nanowires there are both surface enhanced Raman scattering (SERS) and tip enhanced Raman scattering (TERS). The new observations not only enlarge the range of SERS applications, but also imply a possible new enhancement mechanism. Otherwise the Raman and SERS frequencies of SudanII molecule were calculated using, respectively, DFT and B3PW91.