Kinetics of irreversible reactions on platinum single crystal electrodes (III)
- 化学化工－已发表论文 
Based on results of the 1st and 2nd papers of the present studies, the procedure of data processing was developed further. Through the variation of the temperature of the reaction system the apparent Gibbs free energy of activation (Delta G(not equal 0)) for direct oxidation of HCOOH on Pt(100), Pt(111) and Pt(110) single crystal electrodes was obtained for the first time. Under the standard states defined in the present study i.e., at 0.0 V/SCE, 298.15K and 1.013x10(5) Pa, the apparent Gibbs free energy of activation for HCOOH oxidation has been evaluated as 32.2+/-0.5 kJ.mol(-1) on Pt(100), 25.8+/-0.4 kJ.mol(-1) on Pt(111) and 10.1+/-0.2 kJ.mol(-1) on Pt(110), respectively. It has been found that the transfer coefficient (beta) of HCOOH oxidation is independent of temperature in the range between 283.15 similar to 303.15K, but varies with the surface atomic arrangement of Pt single crystal electrode and yields the same variation order as that of the apparent Gibbs free energy of activation.