Experimental Investigation of the Current Distribution on a Recessed Rotating Disk Electrode

Abstract

The design of a recessed rotating disk electrode is described. Its current distribution and mass‐transfer characteristics are compared to those of a rotating‐disk electrode without recess. The ohmic resistance of the recessed‐disk electrode was found to vary linearly with aspect ratio (recess depth/electrode radius). For aspect ratios greater than 0.5, the deviation of the current density at the edge of the electrode from the average current density was less than 10% under conditions of primary current distribution. The mass‐transfer‐limited current varied linearly with the square root of rotation rate up to an aspect ratio of 1.0, but the absolute values of the current decreased with increasing aspect ratio. The mass‐transfer‐limited thickness distribution on plated Cu samples was measured at aspect ratios of 0.1, 0.5, and 1.0. The thickness was uniform near the center of the electrode but decreased rapidly near the edge. The radius at which the thickness began to decrease approached the edge of the electrode as the aspect ratio decreased.

Microhole Array Electrodes Based on Microporous Alumina Membranes

“…As discussed in detail by others (12,15,19,20,30) the shape of the voltammograrn obtained at a microhole electrode is dependant on the scan rate and the depth of the microhole. In a high scan rate experiment, the diffusion layers at the recessed electrodes are confined within the membrane and do not propagate into the bulk solution phase.…”

“…At low scan rates, the diffusion layers created at the recessed Au electrodes will become thicker than the depth of the microhole (12,15,19,20,30). The shape of the voltammogram then depends on whether the solution is stirred or unstirred.…”

Microgalvanics: locally resolved concentration measurements with ion-selective microelectrodes and chronoamperometric microelectrodes

“…All measurements are performed in unstirred solution and no convective influence was observed during measurement. Investigations concerning convective mass transport during electrolysis in microstructures are found in [6] and [7]. Convection due to differences of density within the solution appear only if a high current density is applied for a long time.…”

Electrodeposition Science and Technology in the Last Quarter of the Twentieth Century

“…Using these principles, a number of new designs for electroplating cells were developed in recent years. They include the rotating cylinder Hull cell, 75 the uniform injection cell, 76 the recessed rotating disk electrode 77 and different types of jet cells with submersed or emerged electrolyte jets. [78][79][80][81] The paddle cell 82,83 developed for through mask plating of wafers on a laboratory or industrial scale offers a uniform current distribution over the entire surface.…”