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The voltammetry at three micro-mesh electrodes is explored. It is found that at sufficiently short experimental durations, the micro-mesh working electrode first behaves as an ensemble of microband electrodes, then follows the behaviour anticipated for an array of diffusion-independent micro-ring electrodes of the same perimeter as individual grid-squares within the mesh. During prolonged electrolysis, the micro-mesh electrode follows that behaviour anticipated theoretically for a cubically-packed partially-blocked electrode. Application of the micro-mesh electrode for the electrochemical determination of carbon dioxide in DMSO electrolyte solutions is further illustrated.

The one-electron reduction of oxygen was investigated by cyclic voltammetry at a gold microdise electrode in the RTILs, 1-ethyl-3-methylimidazotium bis ((trifluoromethyl) sulfonyl) imide ([EMIM][(Tf)(sub 2)]) and hexyltriethylammonium bis ((trifluoromethyl) sulfonyl) imide ([N (sub 6222][N (Tf)(sub 20]). The study results of the higher viscosity of [N (sub 6222][N (Tf)(sub 2)] in comparison to [EMIM][N (Tf)(sub 2)] due to the structural differences in cationic component.

Electron transfer reactions at, or within, unsupported femtoliter droplet arrays are explored using redox liquid modified electrodes immersed into aqueous electrolytes. The study shows a possibility of using this ilk of modified electrode as femtoscale electrochemical reactors, with applications to the understanding of acoustic emulsification electrosynthetic processes or in the study of biomimetic processes such as photosynthesis.

The cyclic voltammetry response of partially blocked electrodes was modeled finite difference simulations and a method presented for determining currents at electrode surfaces, which have a well-defined geometric blocking pattern. The comparison of theory with experiment suggested that the modeling of hexagonally distributed blocking systems was superior to that of the cubically arranged ones.

The voltammetry of the water-insoluble redox liquids para-N,N,N' ,N'-tetraalkylphenylenediamines at the TAPD/electrode/electrolyte interface is studied. The electrochemically facilitated ion-transfer processes across the interface between aqueous solutions containing different anion species and organic phases are described.

Designs for reusable microelectrodes, which are easy to assemble and so do not require special technical skills or services for their construction, are presented. Three types of microelectrodes are fabricated by lamination of metal foil, wire, and wire grids, producing microband, microdisk, and a linear array of microdisk geometries. The electrodes themselves do not need to be polished prior to their use but are observed to be slightly recessed from the surrounding insulating surface. Good agreement is observed between experimental steady-state voltammetric results in nonaqueous solutions and the relevant analytical theory for the voltammetric current.

Cyclic voltammetry over a wide range of scan rates shows that the apparent reduction potential depends on the scan rate and initial polarization potential. However, in order to determine these effects, the voltammetric behavior of azurin adsorbed at pyrolytic graphite 'edge' plane (PGE) is compared with results obtained using gold electrodes modified with a self-assembled monolayer of hexanethiol or decanethiol.

The osmotic second virial coefficients (OSVC's) are calculated analytically for some molecular models in which the solvent is taken into account explicitly. The studies reveal that the solute-solvent interaction has a determinant influence on the observed Osmotic second virial Coefficient (OSVC) value.

The electro-reduction of carbon dioxide is examined by using linear sweep and cyclic voltammetry in dimethyl sulfoxide electrolyte solutions at polycrystalline gold microdisk electrodes. The kinetic parameters for the reduction process are deduced from this waveshape approach and the charge-coefficient is found to be approximately 0.43 plusmin 0.05.

The influence of extracellular polymeric substances on carbonate mineral growth in natural settings remains one of the most poorly understood contributors to the growth of non‐marine carbonate sediments. The influences of these materials are complicated by their association with living cells creating local microenvironments via metabolism and enzyme production, and by our uncertainty about the extracellular polymeric substances materials themselves. Different mixtures of extracellular polymeric substance molecules may behave in different ways, and differences in the local physical environment may alter how the mixtures influence mineral formation, and even result in different patterns of polymerization. Here, the influence of extracellular polymeric substances on calcite precipitation rate and Mg/Cacalcite in the absence of cells is investigated using extracts of extracellular polymeric substances from temperate fluvial tufa biofilm. The influence is complex, with the concentration of extracellular polymeric substances in solution altering deposition rate and trace element incorporation. Moreover, the results show interaction of the presence/absence of extracellular polymeric substances and both temperature and salinity. However, despite extracting extracellular polymeric substances from the same parent sample, a uniform influence was not found in these experiments, implying that the mixture is sufficiently variable within a sample for microenvironments within the biofilm to either promote or inhibit mineralization. As sedimentologists, we can no longer take the view that extracellular polymeric substances are a bystander material, or that they have a single set of coherent and predictable or intuitive influences. Rather, the emphasis must be on investigating the specific mixtures present in nature, and their complex and dynamic interaction with both mineral surfaces and hydrochemical conditions. [ABSTRACT FROM AUTHOR]

This work presents the electrochemical response of a 2‐(methylthio)phenol glassy carbon based electrode for a promising voltammetric pH sensor in both buffered and low‐buffered solutions. Electropolymerization of the redox species was performed with the resulting polymer presenting a Nernstian response in buffered media, with a sensitivity of 51 mV/pH unit. The effectiveness of the sulfhydryl bond to facilitate proton transfer from the bulk solution to the phenol molecules has been confirmed, providing an accurate pH measurement of 8.28 in sea water media, compared to that measured with a calibrated glass pH probe of 8.30. [ABSTRACT FROM AUTHOR]