Direct observations of electrochemical reactions within Au-YSZ thin films via absorption shifts in the an nanoparticle surface plasmon resonance

作者：Rogers Phillip H; Sirinakis George; Carpenter Michael A^*

来源：Journal of Physical Chemistry C, 2008, 112(17): 6749-6757.

DOI：10.1021/jp712007f

The surface plasmon resonance (SPR) band of Au nanoparticles embedded in an YSZ matrix was monitored at 500 degrees C under varying gas exposure concentrations of H-2 and O-2 in N-2. Because the peak position of the SPR band relies closely on the number of driven oscillating free electrons per gold nanoparticle, we were able to monitor electrochemical charge transfer from Au nanoparticles to diffusing oxygen ions by monitoring the optical properties of the Au-YSZ nanocomposite thin film, specifically the peak position of the SPR band. A direct relation was observed for the change in the equilibrium ratio, PH21/4/po(2)(1/8), contributing to oxygen ion diffusion into and out of the YSZ matrix, and the change in the square of the SPR band peak position. Free electron theory states that this change in the square of the SPR band peak position is directly proportional to the change in conduction electrons available per Au nanoparticle; thus, our observations agree with the expected trend for charge transfer vs the redox gas mixture.

• 出版日期2008-5-1