Properties electrodeposited multilayers

By way of illustration, it should be noted that modem electrodeposition equips the practitioner with the ability to predesign the properties of surfaces, and in the case of electroforming, those of the whole part. Furthermore, the ability to deposit multilayers of thicknesses in the nanometer region, via electrochemical methods, represents yet a new avenue of producing new materials. 

It should be emphasized here that multilayered laminar metal structures could be obtained by electrodeposition of individual metal layers from separate baths, which is a time-consuming process. On the other side, it is possible to obtain such electrodeposit from one bath containing ions of both metals by appropriate choice of metal ion concentration and applied current density. Hence, by appropriate choice of electrodeposition conditions, one can adjust the composition and the thickness of each layer and, accordingly, properties of such structures. 

Mechanical properties of multilayered structures were only investigated for electrodeposits containing Cu/Cu-Ni layers. Following mechanical properties were mainly investigated Young s modulus [58], hardness [75], and tensile strength [67,75-77]. It was shown that all investigated properties depend on the thickness of the individual layers and that in all cases multilayered structures showed better properties than that of pure metals and/or their alloys. 

Tench M, White J (1991) Tensile properties of nanostmctnred Ni-Cu multilayered materials prepared by electrodeposition. J Electrochem Soc 138 3757-3758... 

Meneyes S, Anderson DP (1990) Wavelength-property cmrelation in electrodeposited ultrastructured Cu-Ni multilayers. J Electrochem Soc 137 440-444... 

The LBL deposition of polymer layers incorporating metal nanoparticles was employed to study the electrochemical properties of the resultant composite films by using SECM. Wittstock and coworkers electrodeposited Pd and Pt nanoparticles in the matrix of LBL-deposited multilayers of polyelectrolytes, that is, polyfdiallyldimethylammonium) and poly(4-stylene sulfonate). The production of hydrogen peroxide during the ORR at the nanoparticle-incorporated LBL films was monitored in the SG/TC mode. The transient current at a 25 pm diameter Pt SECM tip was measured at various tip-substrate distances and quantitatively analyzed to determine effective rate constants 2, and k, for the following reactions at the film ... 

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