Abstract: Kinetics and mechanism of hypophosphite oxidation on a nickel electrode were studied by means of the electrochemical mass spectroscopy (EMS) and kinetic model analysis. In the kinetic model, the electrooxidation of hypophosphite undergoes an H abstraction of hypophosphite from the P－H bond to form the phosphorus-centered radical, PHO2－•,which subsequently is electrochemically reacted with water to form the final product, phosphite. The kinetic equations were derived, and the kinetic parameters were obtained from a comparison of experimental results and the kinetic equations. The process of hypophosphite electrooxidation on a nickel electrode could be well simulated by this model.

Key words: Kinetics, Mechanism, Hypophosphite, Electrooxidation, Nickel electrode