Kinetics and Characteristics of Electrocatalytic Oxidation of Formic Acid on Pt(110)/Sb Electrodes

The electrochemical behavior of irreversibly adsorbed antimony on Pt(110) was studied by using cyclic voltametry. The results demonstrated that the Sbad atoms are stable on Pt(110) when the electrode potentials are below 0. 45 V (vs. SCE). We illustrated that various coverages of Sbad can be easily obtained by controlling the number of potential cycling and the upper limit of potential scan. It was found that the dissociative adsorption of formic acid was inhibited by the presence of Sbad on Pt(110) surface. The electrocatalytic effects of Sbad toward HCOOH electrooxidation is demonstrated by the negative shift of oxidation potential (about 0. 35 V) and the enhancement of oxidation current. The maximum current density was measured for a Sb coverage of 0.126. Based on methods developed in our previous papers, the kinetics of HCOOH electrooxidation on Pt(110)/Sb electrodes of different θSb has been studied, and both the rate constant kf and transfer coefficient β were determined quantitatively.