Chapter 17, Problem 17.28P

Interpretation Introduction

Interpretation:

The current density and thickness of diffusion layer of rotating disc electrode has to be calculated.

Concept introduction:

Current density is defined as current in the unit area of surface of electrode.  It is given as

$\text{Current}\text{density}\text{=}\text{0}{\text{.62nFD}}^{\frac{\text{2}}{\text{3}}}{\text{ν}}^{\text{-}\frac{\text{1}}{\text{6}}}{\text{ω}}^{\text{0}\text{.5}}{\text{C}}_{\text{o}}$

F is faraday constant.

D is diffusion coefficient.

n is number of electrons transported in half reaction.

${\text{C}}_{\text{0}}$  is concentration of electroactive species

The thickness of diffusion layer is given as

$\text{δ}\text{=}\text{1}\text{.61}{\text{D}}^{\text{1/3}}{\text{ν}}^{\text{1/6}}{\text{ω}}^{\text{-0}\text{.5}}$