Electron concentration growth condition dependence

Let us explain what happens with the formation of a bubble. When the electrocatalytic reaction occurs with the production of a gaseous product, it dissolves in the electrolyte until it reaches saturation. It is transported from the electronic conductor to the ionic conductor only by convective diffusion. When the solution concentration exceeds supersaturation, we are able to activate the nucleation sites to the bubble formation. This condition depends on the morphology of the surface and the kind of electrolyte and its viscosity. The growth of the bubble induces a microconvective flow on the electrolyte, pushing in various radial directions each bubble from an ideal center of the surface ( active site ). When each bubble attains a certain size, the buoyancy exceeds its adhesion and the bubble leaves the surface producing a drag flow. 

The presented electrochemical measurements prove that formation conditions sensitively affect the electronic film properties. Consequently, the formation conditions can be used for an adjustment and control of electronic properties to a certain extent. For instance, in the case of Ti/Ti02 changing from potentiody-namic to potentiostatic formation, conditions allows for significant reduction of the donor defect state concentration. Moreover, under potentiodynamic conditions, a pronounced texture dependence of oxide growth is observed, which can be significantly suppressed by potentiostatic formation. The texture dependence itself... 

According to the basic statement of the models we are going to summarize, the metal is conceived as a network of cations immersed in a cloud of free electrons in a crystalline structure. The transport of the ions controls the growth of the new phase (Figure 8.2). The ionic transport will depend on the nature of the system and on experimental conditions, such as temperature, local electric field, local concentration excess, etc. To better understand the continuous-film models, the main ionic transport mechanisms in crystalline solids are presented [1] as follows. 

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