An improved model of the Tafel method for determining the intrinsic kinetic parameters of porous rotating disk electrodes

Rotating disk electrodes with porous layers are commonly used to obtain the oxygen reduction reaction kinetic parameters. In this paper, to eliminate the severe error in the intrinsic reaction kinetic measurement of porous layers of the rotating disk electrode, a flow-electrochemical multi-physical model with porous electrode layer is developed for the detailed simulation of the mass transfer and electrochemistry reaction process. The multi-physical model is solved by finite element method, whose results are validated with the porous electrode layer generated by NGHMs. It turned out that the multi-physical model can reproduce the results of physical experiments by fitting the effective diffusion coefficient in the porous structure. Based on this model, the classical Tafel method is improved, so that it can be applied to porous electrodes and more accurate intrinsic reaction kinetic parameters can be obtained as a result. All of the above proves that the measurement accuracy of the electrocatalytic performance of porous rotating disk electrode can be greatly enhanced.