Hydrogen electrode 264 INDEX

We can measure the pH of an unknown solution if two hydrogen electrodes are immersed into two solutions of differing hydrogen ion concentrations, the [H" ] being constant in one of these solutions. The electromotive force developed in such a system will be an index of the [H ] in the unknown solution. If we consider the potential of norm hydrogen electrode as Eh, and that of the hydrogen electrode in the unknown solution as Eh, the e.m.f. obtained on completing the circuit will be... 

The multi-wavelength ellipsometiy (i.e., spectroscopic elhpsome-try) can characterize spectroscopic property of the passive oxide. Figure 24 indicates spectra of the complex refractive index, N2 = 2 - j 2, of the passive oxide formed on iron at 1.43 V vs. reversible hydrogen electrode at the same solution (RHE) in pH 8.4 borate solution and in pH 3.1 phosphate solution for 1 In Fig. 24, the thickness of the passive oxide was estimated at each wavelength of incident light. The measurement and estimation were made by the 3-parameter method. Similar results were also reported by Cahan et al. " ... 

Hoshi et al. extended the formation of reduced CO2 at Pt single crystal electrode to those of high index crystal orientations. They determined the initial rate of CO2 reduction Vt=Q from the slope of the time course of adsorbed CO formation at t = 0 as shown in Fig. 17. Figure 18 shows dependences of on the electrode potential at a series of electrodes Pt(S)-[ 7(111) X (111)] in 0.1-M HCIO4. The electrode surfaces are composed of n atomic rows of (111) terrace and one atomic height of (111) step. Adsorbed hydrogen is present below 0.3 V vs. re-... 

The interplay of hydrogen-bonded dimers and substrate-adsorbate coordination is a general property of aromatic carboxyUc acids on low index gold single crystal electrodes. 

Figure 10.9 In-situ IR spectra (SNIFTIRS) of high-index planes of Pt in 0.5 M H SO,. All spectra recorded atOV (RHE) with a reference potential of 0.8 V [16], Reprinted from Surface Science, Vol. 605, Nakamura, M. Kobayashi, T Hoshi, N. Structural dependence of intermediate species for the hydrogen evolution reaction on single crystal electrodes of Pt, pages 1462-1465, copyright 2011, with permission from Elsevier.

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