Rotating ring-disk electrode voltammetry

The iron complex (23) adsorbed on graphite electrode surfaces is an active catalyst for the electroreduction of both nitrite and nitric oxide to yield NH2OH and NH3, as demonstrated by rotating ring-disk electrode voltammetry experiments.341... 

Data on the electrochemistry of the telluride ion in alkaline media are relatively limited. Mishra et al. [53] studied the oxidation of Te to Te° at solid electrodes, focusing on the intermediate step(s) of this process, and in particular, the possibility of detecting ditelluride Te via rotating ring disk electrode (RRDE) methodology. Oxidation beyond the elemental state to TeO and TeO was also studied using cyclic and hydrodynamic voltammetry. 

Another type of polymeric structure is based macrocyclics or on stacks of macro-cyclic units. An exhaustive electrodynamic investigation of the polymer derived from yU.-oxo-(tetra-ferf-butylphthalocyaninato)germanium and of the monomer was carried out using CPE, CV, voltammetry by RDE, rotating ring-disk electrode and differential pulse... 

Voltammetry at Rotating Disk and Rotating Ring-Disk Electrodes... 

Another voltammetric method, rotating ring-disk electrode (RRDE) voltammetry, was applied to study the same reaction and excellent agreement was found with the DPSC results. The studies were conducted at temperatures as low as -78°C and at rotation rates between 500 and 6000 rpm. Unlike DPSC, analysis of the RRDE data required knowledge of both the kinematic viscosity of the solution and the diffusion coefficient of the reactant at each temperature, so it was necessary to measure these quantities to complete the analysis. 

Hydrodynamic electrodes — are electrodes where a forced convection ensures a -> steady state -> mass transport to the electrode surface, and a -> finite diffusion (subentry of -> diffusion) regime applies. The most frequently used hydrodynamic electrodes are the -> rotating disk electrode, -> rotating ring disk electrode, -> wall-jet electrode, wall-tube electrode, channel electrode, etc. See also - flow-cells, -> hydrodynamic voltammetry, -> detectors. 

Many interesting processes occurring at the liquid/liquid interface involve coupled homogeneous chemical reactions. In principle, electrochemical methods used for probing complicated mechanisms at metal electrodes (61) can be employed at the ITIES. However, many of these techniques (e.g., rotating ring-disk electrode or fast-scan cyclic voltammetry) are hard to adapt to liquid/liquid measurements. Because of technical problems, few studies of multistep processes at the ITIES have been reported to date (1,62). 

Table 6.4 gives the output of Program 5 under certain conditions. We see that for a layer thickness z/ = 2.5 x 10" cm, Program 5 finds a value of Hip close to that obtained by other techniques [Table 6.4(a)]. Orthogonal collocation is used to simulate rotating ring disk electrodes and cyclic voltammetry for CE and EC mechanisms. Furthermore orthogonal collocation is used to characterize diffusion at microelectrodes and microelectrode arrays. ... 

Ordinarily, the selectivity of ORR is determined by means of rotating disk electrode (RDE) or rotating ring-disk electrode (RRDE) voltammetry. The RDE is designed to boost the diffusion of an electroanalyte in conditions where an electrochemical reaction is limited by diffusion of the analyte to the electrode. In RRDE, a ring (often platinum) surrounds the disk electrode with an insulating material (usually Teflon) between them (Fig. 7.5). 

Cyclic voltammetry (CV), rotating disk electrode (RDE), and rotating ring-disk electrode (RRDE) in a traditional tri-electrode cell are often employed in the study of the ORR kinetics and mechanisms on various catalysts in liquid electrolytes [27, 28]. As shown in Fig. 15.2, a tri-electrode cell contains a working electrode (WE), a reference electrode (RE), and a counter electrode (CE). The CE has much... 

---