Aluminum surface morphology

In Fig. 1 AFM images of aluminum surface and surface profile positioned along a white line at 2D image measured with Ill-type cantilevers are presented. The sharpest cantilever of Ill-type allowed us to obtain a real image of aluminum surface. Morphology of the real surface of anodic treated aluminum contains sharp tips constructed at the intersection of the neighboring cell walls. The aluminum tip radius is about 2 nm. By this reason cantilevers of I-st and Il-nd type couldn t show real picture of the tips on aluminum surface. 

Fig. 34. PAA aluminum surface covered with a thin layer of grease that masks the oxide morphology.

The SEM micrograph of Figure 12.1 shows the surface morphology of an electroplated aluminum layer obtained at a current density of—20mAcm-2 for 2h in Lewis acidic [EMIMJCl/AlClj at room temperature on mild steel. As can be seen, the obtained A1 deposit consists of coarse crystallites forming rather a compact layer without observable cracks. 

The SEM micrograph of Figure 12.7(a) shows the surface morphology of a deposited aluminum layer obtained galvanostatically at a current density of—5 mAcrn-2 for 2h in the upper phase of the biphasic mixture [EMIM] TFSA/6M AICI3 at room temperature. Prior to Al electrodeposition, the electrode was anodically polarized at a potential of 1V (vs. Al) for 2 min. As seen, the deposited Al layer is dense and contains crystallites in the micrometer regime. 

Crystals of NaA zeolite showed strong cubic habits typical of these structures (Figure 3). The surface morphology of the 0.3pm crystals of ZSM-5(9) was usually irregular (Figure 4) and seldom exhibited crystal facets. The 2pm crystals of ZSM-5(40) showed facets typical of ZSM-5 of moderate aluminum content (Figure 5). 

After anodization and subsequent selective dissolution of anodic oxide the aluminum surface is a replica of back side of anodic alumina. Such surfece structure has ultrasharp tips with 20-100 nm height distanced ixom 10 to 500 nm, respectively. It is obvious that external part of anodic alumina has tip-like morphology too. However partial tip dissolution and smoothing during anodization in acidic solutions results in increasing of tip radii [4]. Thus taking into account known experimental results and our observations it can be concluded that the proposed approach allows to form sharp tips. 

Jiang et al. studied the electrodeposition and surface morphology of aluminum on tungsten (W) and aluminum (Al) electrodes from 1 2 M ratio of [Emim]CI/AlCl3 ionic liquids [165,166]. They found that the deposition process of aluminum on W substrates was controlled by instantaneous nucleation with diffusion-controlled growth. It was shown that the electrodeposits obtained on both W and Al electrodes between -0.10 and -0.40 V (vs. AI(III)/A1) are dense, continuous, and well adherent. Dense aluminum deposits were also obtained on Al substrates using constant current deposition between 10 and 70 mA/cm. The current efficiency was found to be dependent on the current density varying from 85% to 100%. Liu et al. showed in similar work that the 20-pm-thick dense smooth aluminum deposition was obtained with current density 200 A/m for 2 h electrolysis [167],... 

Jiang T, Cholher MJ, Brym B (2006) Electrodeposition of aluminum from ionic liquids part i - electrodeposition and surface morphology of aluminum from etluminium chloride ([EMIm] Cl) ionic liquids. Surf Coat Technol 201 1-9... 

Based on the results from Karavasteva [7], it seems that the kinetics and consequently the surface morphology of the deposited copper via the galvanic displacement reaction onto zinc, iron, and aluminum are strongly influenced by... 

It seems that the surface morphology of the deposited copper onto Al, Fe, or Zn is strongly influenced by the rate of dissolution of these metals and by the nature of these substrates [7], as noted in the previous section. Globular crystallites pm in size are obtained on aluminum, while a coherent layer of fine crystallites less than... 

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