Electrochemical Crystallization of Plasmonic Nanostructures

• Published in: Nano letters 2011-03, Vol.11 (3), p.1337-1343
• Main Authors: Dahlin, Andreas B, Sannomiya, Takumi, Zahn, Raphael, Sotiriou, Georgios A, Vörös, Janos
• Format: Article
• Language: English
• Subjects: Collective excitations (including excitons, polarons, plasmons and other charge-density excitations); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Crystallization; Electrochemistry - methods; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Methods of nanofabrication; Microscopy, Atomic Force; Microscopy, Electron, Scanning; Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals; Nanostructures; Physics; Structure of solids and liquids; crystallography; Surface and interface electron states; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl104424q

We show how gold recrystallizes when under the influence of electrochemical potentials. This “cold annealing” occurs without charge transfer reactions and preserves nanoscale structural features. By performing the process on plasmonic nanostructures, grain growth is monitored noninvasively by optical spectroscopy. In this way, the influence from crystal structure on plasmon resonances can be investigated independently. Observed spectral changes are in excellent agreement with analytical models and changes in electron relaxation time and plasma frequency are calculated.