Deposit morphology temperature effect

In [61], the influence of the nickel(II) concentration on the deposition process, in [62], the influence of potential on deposit morphology, while in [63], the morphology and structure of nickel nuclei as a function of the conditions of electrodeposition were studied. In the latter, the effects of growth rate (affected by the temperature and/or the nickel concentration), bath composition, and deposition time (particularly at low overpotentials) on the morphology of nickel nuclei were analyzed. 

Another prediction of the model is that the size and number of particles are uniquely determined by the total amount of material deposited, irrespective of conditions, provided complete condensation is operative. This can be readily appreciated by noting that, in Equations (9) and (10), time appears only in conjunction with rate so that Vt (the quantity deposited) is the effective independent variable. This prediction has been verified through experiments in which rate and temperature were varied for a given specimen. The deposit morphology depended only on how much material was deposited and was insensitive to the way in which it was done. 

Fig. 8. Morphological effects of supersaturations and temperature on vapor deposited materials (12).

Extensive studies of the acidity and basicity of zeolites by adsorption calorimetry have been carried out over the past decades, and many reviews have been published [62,64,103,118,120,121,145,146,153,154]. For a given zeolite, different factors can modify its acidity and acid strength the size and strength of the probe molecule, the adsorption temperature, the morphology and crystallinity, the synthesis mode, the effect of pretreatment, the effect of the proton exchange level, the Si/Al ratio and dealumination, the isomorphous substitution, chemical modifications, aging, and coke deposits. 

The motivation of this chapter was to show that despite the enormous prospects of ionic liquids in electrodeposition some troublesome aspects have to be expected. Apart from the purity and price of ionic liquids the optimum temperature for any process has to be found. Furthermore, suitable additives for electrodeposition will have to be developed and cation/anion effects that can strongly alter the morphology of deposits have to be expected. Finally, the electrochemical window alone is not the only factor that needs to be considered for the deposition of reactive metals. Suitable precursors will have to be tailor-made and it is our personal opinion that the electrodeposition of metals like Mg, Ti, Ta and Mo may not be possible from metal halides but rather metal bis(trifluoromethylsulfonyl)amide salts and other ones may be more suitable. 

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