Electrochemical Tuning of Localized Surface Plasmon Resonance in Copper Chalcogenide Nanocrystals

LLORENTE, VICTORIA BENAVENTE; DZHAGAN, VOLODYMYR M.; GAPONIK, NIKOLAI; IGLESIAS, RODRIGO A.; ZAHN, DIETRICH R. T.; LESNYAK, VLADIMIR

JOURNAL OF PHYSICAL CHEMISTRY C

AMER CHEMICAL SOC

Año: 2017 vol. 121 p. 18244 - 18244

1932-7447

n this work, we developed a method to study in situ the optical properties of Cu2-xSe and CuS nanocrystals upon electrochemical reduction and oxidation. Both these materials possess a strong localized surface plasmon resonance (LSPR) in the near-infrared region. First, the nanoparticles were embedded into a transparent film made of a perfluorinated sulfonic-acid copolymer Nafion deposited onto an ITO-coated glass. This substrate was employed as a working electrode for chronoamperometry and cyclic voltammetry measurements directly in a transparent cell allowing for simultaneous acquisition of absorption spectra of the system upon its charging/discharging. We observed that LSPR of the Cu2-xSe NCs can be well-controlled and tuned in a wide range simply by potentiostatic potential switching. Starting with an intensive plasmon of the initial as-synthesized Cu2-xSe NCs we were able to completely damp it via reduction (electron injection). Moreover, this electrochemical tuning was demonstrat