ROTATING-DISK ION-SELECTIVE ELECTRODES

A simulation was undertaken to predict the transient potential respons e following a concentration step at a rotating disk electrode comprise d of an inn selective layer. A basis for this simulation was that the potential response would be independent of rotation rate since the dif fusion layer is larger than the double layer at the electrode. in prac tice it was found that the potential response does vary with rotation rate. The response was such that the apparent concentration of the ana lyte in solution decreased with increased rotation rate. The reason fo r this behavior is due to the disruption of the double layer at the el ectrode surface by convection.