A new equivalent circuit model for porous carbon electrodes in charge transfer reaction of iodide/triiodide redox couples

作者：Kwon Woosung; Kim Jung Min; Rhee Shi Woo^*

来源：Electrochimica Acta, 2012, 68: 110-113.

DOI：10.1016/j.electacta.2012.02.056

• Equivalent circuit models
• Carbon counter electrodes
• Electrochemical impedance spectroscopy
• Dye-sensitized solar cells

In this research, a new equivalent circuit for porous carbon electrodes is proposed. In order to analyze the validity of the new model, electrochemical impedance spectra of carbon black (CB) electrodes in a symmetric cell configuration are examined by varying the CB particle size and the electrode thickness. This model decouples and identifies the following elements: (i) the electron transport resistance and trap capacitance in the CB layer, (ii) the charge transfer resistance and the double layer capacitance, and (iii) the Nernst diffusion impedance at the electrode/electrolyte interface. The fit quality is quantified by the chi-square test, and the fit data show consistency with the measured conductivity, surface area, and thickness of the CB electrode.

• 出版日期2012-4-30