Real surface area measurements in electrochemistry

The correlation of electrochemical and fuel cell results for alcohol oxidation in acidic and alkaline media

“…EASA determination of electrodes having only one metal are relatively straight forward and is well described for each metal [14]. Firstly, in the special case of Pt electrode the EASA can be determined through the hydrogen adsorption from the electrolyte onto the Pt surface.…”

“…For this method it is commonly assumed that the adsorption process of H UPD on Pt surface is a 1:1 (i.e. a hydrogen atom will adsorb on each Pt sites) [14] and that the charge required for adsorption on polycrystalline Pt to form a monolayer is Q H,mono = 210 µC cm 2 . This value is estimated with the assumption that the density of the atoms is 1.31 x 10 15 cm -2 [15,16] pertaining to the (100) face of the Pt electrode [17].…”

“…Whereas Pd electrode exhibits an indefinable hydrogen adsorption region, as seen in Figure 5, and therefore the hydrogen adsorption method cannot be accurately used for the EASA determination. Instead, reduction of PdO x is commonly utilized [14,[22][23][24][25].…”

On-line characterization of platinum/graphite catalysts during liquid phase oxidations using cyclic voltammetry

“…1019 m -2 [35]. All measured fractions of exposed platinum atoms are reported in terms of the platinum particle size as calculated from Eq.…”

“…The part of the cyclic voltammogram ranging from 0 to 0.4 V corresponding to the reductive adsorption of protons in the cathodic scan and the subsequent oxidation of the hydrogen adatoms in the anodic scan is called the hydrogen region. The degree of hydrogen coverage ranges from zero at 0.4 V to monolayer coverage at 0 V. The surface area of the platinum metal can be determined from the charge associated with the anodic oxidation of the monolayer of hydrogen adatoms taking place between 0 and 0.4 V. Assuming a Pt:H stoichiometry of 1:1 and a platinum number surface density of 1.31 • 1019 m-2, 2.1 C m-2 is transferred during the oxidation of a monolayer of hydrogen adatoms [35]. The dashed line represents the non-faradaic current, which is not caused by the oxidation of adsorbed hydrogen.…”