Theoretical evaluation of the collection efficiency at ring-disc microelectrodes

Dual-microdisk electrodes in transient generator–collector mode: Experiment and theory

“…Such measurements can also be operated in transient mode, where 'time of flight' experiments reflect, in a highly sensitive manner, both the diffusion coefficient and the homogeneous chemical reaction rates of electro-generated species; such experiments are normally conducted with a potential step at the generator electrode with the collector current measured at a potential corresponding to a transport limited detection of the product or intermediate of interest. These systems have been studied extensively in terms of two dimensional diffusion, where the collector and generator are both parallel microbands [25][26][27][28][29][30], channel electrodes [27,31,32], walljet electrodes [33,34], or at a ring-disk electrode [35][36][37][38][39][40][41][42][43]. To a lesser extent, due to the stimulatory three-dimensional nature of the system, the dual-microdisk generator collector system has also been probed [23,24,36,44], as well as dual micro-hemispheroidal electrode systems [24,45,46].…”

Microelectrode systems for the study of photochemical processes in solution

“…Not only is the incident light distribution non-uniform, but it is not clear how the light would be dispersed on entering the solution, which is clearly vital in the CFMR case given that the ring electrode sits at the boundary between the illumination zone and the dark at the plane at which light enters the system. Second, the CFMR model considers a coplanar 'perfect' ring that is very difficult to obtain, as previously reported [59], especially when an insulating material like epoxy resin is used [15]. Third, there may be some complications from natural convection for ring microelectrodes of this size as highlighted by Amatore et al [60] and in our previous studies [45].…”

“…For example, the micro-optical ring electrode (MORE) was used to detect electro-active species with lifetimes <9 Â 10 À5 s [11] and to study photoelectrochemical kinetics [12]. Ring electrodes are characterised by well-defined mass-transport in quiescent solution [14][15][16][17][18] and this is a particularly attractive feature of MOREs.…”

Theory of Anodic Stripping Square Wave Voltammetry on Spherical Mercury Electrodes

“…[6][7][8][9][10] These electrodes are characterized by high mass transport density, small double-layer capacitance, small ohmic drop and steady-state current response in unstirred solutions. [11][12][13][14][15] Thus, in the preconcentration step of stripping technique no agitation of solution is necessary. 2,4,9,11,12 The concentration of amalgam forming ions can be measured by anodic stripping voltammetry on mercury microelectrodes.…”