3D Printed Rotating Acentric Binary-Disk Electrode.

Rotating ring-disk electrode (RRDE) is a generator-collector electrochemical system widely used as an electroanalytical and kinetic device. However, RRDEs are costly and difficult to fabricate, particularly when the electrode material is fragile, small, and scarce. Taking advantage of readily available 3D printing technology an alternative generator-collector system was developed: rotating acentric binary-disk electrode (RABDE). RABDE consists of two close acentric disk electrodes arranged in a cylindrical matrix so that the line connecting their centers is perpendicular to radius of the device passing through the center of generator electrode. In contrast to RRDE that is based on radial flow velocity for mass transfer between the generator and the collector, RABDE mostly takes advantage of the larger tangential flow velocity. RABDE thus exhibits higher current densities than RRDE for a same rotation rate and evidences much better electroanalytical performances. These increased performances were tested and quantified using typical analytes: potassium ferricyanide system, copper ion system, and oxygen reduction reaction in alkaline solution.