Rotating disk electrode improvements with

The quantitative and qualitative analysis presented in Section 20.2.1 demonstrates that the finite-diffusion-layer model provides an inadequate representation for the impedance response associated with a rotating disk electrode. The presentation in Section 20.2.2 demonstrates that a generic measurement model, while not providing a physical interpretation of the disk system, can provide an adequate representation of the data. Thus, an improved mathematical model can be developed. 

C) (110) orientations. (D) Polarization curves obtained from rotational disk electrode (RDE) measurements in 0.1 M HCIO4 at 333 Kat 1600 rpm with 50 mV s PtsNidll) (bold), Pt(111) (long dashed), and Pt-poly (dashed). Reprinted from Science, 315, 493 (2007), Vojislav R. Stamenkovic., Improved oxygen reduction activity on PtsNillll) via increased surface site availability, 493-497, 2007, with permission from Sciencemag. 

The ORR has been studied with a rotating ring-disk electrode (RRDE), which can provide theand the H2O2 yield P(H202) at around room temperamre. However, for improving the ORR activity, PEFCs should be operated at high temperature (> 80 °C). In this section, we demonstrate the temperature dependencies of ORR activity and P(H202) at pure Pt (both bulk and supported catalyst) and bulk Pt alloys (Pt-Ni, Pt-Co, and Pt-Fe). 

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