Effect of temperature on the diffusion current and the thickness of the diffusion layer

Abstract

1. An investigation was made of the effect of temperature on the limiting diffusion current and the thickness of the diffusion layer at copper, iron, and amalgamated copper electrodes in stirred and unstirred solutions of sodium chloride and ferric chloride. 2. In unstirred electrolytes at constant oxygen concentration the limiting diffusion current increases with temperature. When the concentration of oxygen changes as a result of reduction of solubility with rise in temperature, the limiting current attains its maximum value at 80° and then falls. 3. In a stirred electrolyte the thickness of the diffusion layer increases with rise in temperature. In unstirred electrolytes δ diminishes with rise in temperature as a result of increased convectional mixing. 4. At iron and copper in N NaCl oxygen is reduced partly to hydrogen peroxide and partly to hydroxyl ions.