Kinetics and characteristics of electrocatalytic oxidation of formic acid on Pt (110)/Sb electrodes

The electrochemical behavior of irreversibly adsorbed antimony on Pt(110) w as studied by using cyclic voltametry. The results demonstrated that the Sb -ad atoms are stable on Pt (110) when the electrode potentials are below 0. 45 V (vs. SCE). We illustrated that various coverages of Sb-ad can be easil y obtained by controlling the number of potential cycling and the upper lim it of potential scan. It was found that the dissociative adsorption of form ic acid was inhibited by the presence of Sb-ad on Pt (110) surface. The ele ctrocatalytic effects of Sb-ad toward HCOOH electrooxidation is demonstrate d by the negative shift of oxidation potential(about 0.35 V) and the enhanc ement of oxidation current. The maximum current density was measured for a Sb coverage of 0.126. Based on methods developed in our previous papers, th e kinetics of HCOOH electrooxidation on Pt(110)/Sb electrodes of different 0(Sb) has been studied, and both the rate constant k(f) and transfer coeffi cient beta were determined quantitatively.