Formic acid oxidation cyclic voltammograms

Fig. 25. Cyclic voltammogram of formic acid oxidation on Pt(100) in a 0.05 M HCOOH, 10-3 M HC104 electrolyte solution. In this experiment, an external resistance (i x = 600 Q) was used scan rate 5 mV s-1. (Reproduced from P. Strasser, M. Liibke, F. Raspel, M. Eiswirth and G. Ertl, J. Chem. Phys. 107 (1997) 979-990, by permission of the American Institute of Physics.)...

Figure 24. (a) Experimental cyclic voltammogram of formic acid oxidation on Pt (111) with external resistance430 1. Electrolyte 0.05 M HCOOH, lO M HCIO4. Scan rate 5 mV/s. (After Strasser et al. (b) Calculated cyclic voltammogram and stationary current-voltage curve for the formic acid model [Eq. (15)]. A smaller trppjggjjWas chosen than the one used in Fig. 22(a). The anodic and cathodic scans are indicated by arrows. The dashed line shows the portion of the stationary state curve that corresponds to unstable steady states. (After Strasser et al. with permission of the authors.)... 

Besides methanol and ethanol, only a few other small molecules (HCOOH, HCHO, CO), have been oxidized at electron conducting polymer electrodes modified by incorporation of platinum microparticles. The first study on formic acid oxidation at Pt particles dispersed in a PAni matrix was carried out, as early as 1986, by Gholamian et al. [57], They found that the incorporation of 100 pg cm of Pt into PAni was sufficient to enhance considerably the oxidation rate of formic acid (ten-fold increase). The cyclic voltammograms recorded with 0.5 M HCOOH in 0,5 M H2SO4 displayed an enhanced oxidation current particularly for the first oxidation peak at 0.2 V/SCE, attributed to the oxidation of the weakly adsorbed intermediate (reactive species). The second peak, at 0.6 V/SCE, attributed to the oxidation of the strongly chemisorbed... 

Figure 6 Peak turnover rates (reactions per bare platinum atom per second) for formic acid oxidation on Pt(lll) as a function of carbon coverage. The data were obtained from cyclic voltammograms (squares - positive sweep circles -negative sweep) at 50 mV/s in 0.1 mol/dm HCOOH plus 0.1 mol/dm HCIO. The lines are guides to the eye.

Fig. 22 Cyclic Voltammograms for formic acid oxidation at smooth polycrystalline platinum, without addition (dotted lines) and with lead ions in the electrolyte (full lines) 1 M HCOOH/1 M H2SO4, M Pb +,...

Figure 6.24. (a) Cyclic voltammogram of electro-oxidation of formic acid on a Pt(100) single-crystal showing current spikes indicating sustained current oscillations and (b) current oscillations measured at various fixed potentials all potentials are with reference to the Standard Calomel Reference Electrode (SCE) (adapted from [140]). 

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