Granular anodic film

The Cu(100) surface shows in 0.1 M NaOH a similar anodic and cathodic peak both at E = —0.8 V [137] however, no reconstruction of the surface could be found. This is presumably not necessary because the Cu(100) surface is less densely packed in comparison with Cu(lll) and matches already the cuprite structure. Similarly, the close match of the anodic and cathodic peaks without a hysteresis is an additional indication for a faster adsorption process, whereas the surface reconstruction of Cu(lll) with the dilfusion of the Cu atoms to the step edges slows the adsorption process. The anodic film forms at first also a granular structure and a final crystalline film. First STM studies suggest an orientation of Cu(100) parallel to Cu2O(100) with a distance parameter of 0.3 nm which corresponds again to the Cu Cu distance within the cuprite structure. 

Copper can be electro-deposited on to a silvered article the plating bath consists of 10 gm of copper sulphate in 100 gm water. The article is taken from the silvering bath, washed, and put wet in the plating bath—on to a copper cathode so that electrical contact is made to the silver. A copper anode is placed 1-2 cm above the article. The electrodes should be about the same size as the article. The current density should be about 0-05 amp/cm, and in 2-4 minutes a thin copper film should be made. If the current density is too high a granular deposit will be formed which will rub off, and if it is too low a non-uniform deposit will be formed. 

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