Electrical Control of Plasmon Resonance of Gold Nanoparticles Using Electrochemical Oxidation

Autor: Shuichi Uchikoga, Takashi Miyazaki, Hajime Yamaguchi, Haruhi Oh-oka, Isao Amemiya, Ray Hasegawa, Hitoshi Nagato
Rok vydání: 2009
Předmět:
Zdroj: The Journal of Physical Chemistry C. 113:8484-8490
ISSN: 1932-7455
1932-7447
Popis: A large shift of the localized surface plasmon resonance (LSPR) spectrum of gold nanoparticles was attained by electrochemical oxidation of the nanoparticle surface. This oxidation occurred in the cell, which consisted of a pair of indium tin oxide (ITO) electrodes and water medium between the electrodes. On one side of the ITO electrode, the gold nanoparticles were adsorbed. With the application of a voltage of 5 V to the cell, a spectrum shift as large as 68 nm was obtained. Though the spectrum shift has already been observed by changing liquid crystal (LC) orientation surrounding gold nanoparticles, the size of the shift was not large (11 nm). That was because the variation of the effective refractive index of LC was rather small. Our large shift due to electrochemical oxidation resulted from the large refractive index of Au−O. The electrochemical oxidation was confirmed by XPS analysis of the gold nanoparticles with the LSPR spectrum shift. Other possible mechanisms of the shift such as charge localiz...
Databáze: OpenAIRE