An important factor in the cathodic electrodeposition of a base metal (M) is the increase in pH (“alkalization”) of the electrolyte near the cathode.Chemical equilibria and transport processes in the cathodic diffusion layer are analyzed by numerical integration of the transport equations. The analysis shows that alkalization is caused by the production of OH− at the cathode and is prevented when the hydroxyl ions so produced react to form a soluble species (e.g., MOH+ or H2O ).When complex ions are not formed, alkalization occurs if iwδ>boldFDH+ false[H+]o , where inormalw is the hydrogen reduction current, δ is the thickness of the diffusion layer, false[H+]o is the bulk hydrogen ion concentration, and DH+ is the ionic diffusion coefficient for hydrogen. Formation of metal‐hydroxy or metal‐anion complexes can prevent alkalization even when this limit is exceeded. This is illustrated by specific numerical examples.

Potentiodynamic, galvanostatic, and hybrid galvano‐potentiostatic experiments were conducted in O2 saturated 2N H2SO4 on a polished platinum disk electrode. The results show conclusively that for coverage between one and three monolayers the law of anodic growth of oxide film on platinum is precisely the same regardless of the mode of growth (i.e., potentiostatic, galvanostatic, or potentiodynamic). A correspondence is analytically established between galvanostatic and potentiodynamic data, and this correspondence is verified experimentally. Galvanostatic and potentiodynamic data both show that the growth of the oxide film cannot be explained by any mechanism for which false(∂V/∂q)normali is independent of i (e.g., adsorption). The high‐field ionic conduction model accounts for the major features of all the data. A comparison of galvanostatic and hybrid galvano‐potentiostatic experiments shows that there is no aging of the film over a time interval, normalΔt , comparable to the duration of the experiments false(20sec≤normalΔt≤150secfalse) . The effect of “holding” (i.e., interrupting the potential sweep and maintaining a constant potential for a time) during potentiodynamic experiments is explained entirely in terms of the potentiostatic growth of the oxide film during the holding period.

An organic photovoltaic (OPV) device has been used in conjunction with a flexible inorganic phosphor to produce a radiation tolerant, efficient and linear detector for 6 MV X-Rays. The OPVs were based on a blend of poly(3-hexylthiophene-2,5-diyl) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM). We show that the devices have a sensitivity an order of magnitude higher than a commercial silicon detector used as a reference. Exposure to 360 Grays of radiation resulted in a small (2%) degradation in performance demonstrating that these detectors have the potential to be used as flexible, real-time, in-vivo dosimeters for oncology treatments.

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