Chapter 5
Compositionally Modulated
and Multilayered Deposits
5.1 On the Electrodeposition of Nanolaminated Materials
Compositionally modulated alloys (CMA) exhibit an intentional composition modulation along the surface normal (i.e., in the growth direction). In general, any coating
with uneven composition can be classified as CMA. The CMA coating will be called
hereinafter a multilayer when the interface between the layers of distinct composition is relatively sharp and no graded composition zone occurs along the growth
direction with a thickness that is comparable to that of either of these layers. For
such deposits, the term compositionally modulated multilayer coating (CMMC) is
commonly found in the literature. It has to be noted that deposits with layers of alternating structural properties are also called multilayers, even if composition modulation does not necessarily occur here. In such cases, mostly the crystallite size of the
deposit is the modulated parameter.
With the development of the field, various reviews were published either with
a general approach [1–5] or focusing on a particular physical property [6] of the
multilayered deposits. Sections 5.2 and 5.3 will present the basic deposition methods
of CMA materials, while their specific properties will be detailed in Sect. 5.4.
5.2 Multiple-Bath Methods
5.2.1 Common Features of the Multiple-Bath Methods
The advantage of the application of multiple-baths for multilayer electrodeposition
is that the chemical environment in each deposition step is completely unrelated
to that of the other steps. The application of fully independent solutions for the
deposition of each layer in a multilayer structure yields a special degree of freedom
that makes it possible to optimize each single bath used separately, should it be used
to produce a metallic element or an alloy. It can be particularly important to use the
© Springer Nature Switzerland AG 2021
L. Péter, Electrochemical Methods of Nanostructure Preparation,
Monographs in Electrochemistry, https://doi.org/10.1007/978-3-030-69117-2_5
133
Compositionally Modulated
and Multilayered Deposits
5.1 On the Electrodeposition of Nanolaminated Materials
Compositionally modulated alloys (CMA) exhibit an intentional composition modulation along the surface normal (i.e., in the growth direction). In general, any coating
with uneven composition can be classified as CMA. The CMA coating will be called
hereinafter a multilayer when the interface between the layers of distinct composition is relatively sharp and no graded composition zone occurs along the growth
direction with a thickness that is comparable to that of either of these layers. For
such deposits, the term compositionally modulated multilayer coating (CMMC) is
commonly found in the literature. It has to be noted that deposits with layers of alternating structural properties are also called multilayers, even if composition modulation does not necessarily occur here. In such cases, mostly the crystallite size of the
deposit is the modulated parameter.
With the development of the field, various reviews were published either with
a general approach [1–5] or focusing on a particular physical property [6] of the
multilayered deposits. Sections 5.2 and 5.3 will present the basic deposition methods
of CMA materials, while their specific properties will be detailed in Sect. 5.4.
5.2 Multiple-Bath Methods
5.2.1 Common Features of the Multiple-Bath Methods
The advantage of the application of multiple-baths for multilayer electrodeposition
is that the chemical environment in each deposition step is completely unrelated
to that of the other steps. The application of fully independent solutions for the
deposition of each layer in a multilayer structure yields a special degree of freedom
that makes it possible to optimize each single bath used separately, should it be used
to produce a metallic element or an alloy. It can be particularly important to use the
© Springer Nature Switzerland AG 2021
L. Péter, Electrochemical Methods of Nanostructure Preparation,
Monographs in Electrochemistry, https://doi.org/10.1007/978-3-030-69117-2_5
133