Template-assisted electrodeposition

Key words electrodeposition, nanomaterials, pulse and pulse reverse electrodeposition, template-assisted deposition, additives and grain refiners, nanostuctured metals and alloys, nanocomposites, multilayers, biocompatible materials, corrosion resistance of electrodeposited nanostuctured materials. 

Three-dimensionally nanostructured transparent conducting ZnO could serve as electrode for several applications such as dye-sensitized solar cells. Thus, the template-assisted nanopatterning of ZnO via electrodeposition was attempted, following the... 

Next, the template-assisted nanostructured deposition of NiO was tried, following the experimental method of Sonavane et al. for the electrodeposition of nontemplated coatings [62]. For this purpose a 0.5M aqueous NiCl bath containing 0.1 M KCl was prepared, which was complexed using EDTA and pH-adjusted to 8 by addition of KOH. Electrodeposition was conducted in a three-electrode cell at a potential of -1.1 V versus Ag/AgCl for lOOmin. The obtained DG-structure NiO film of about 1 ttm thickness is presented in Fig. 5.5. This preparation technique has two major disadvantages firstly, the very slow deposition rate, and secondly, the transparency of the deposit complicates the anyway difficult preparation route. In Chap. 6, a more elegant approach for nanostructured NiO deposition is presented that overcomes these issues. 

Compared to the electrodeposition of the metal oxides, electroplating of the corresponding metal can have several other advantages when attempting the template-assisted nanopatterning. Metallic nickel plating, for example, is considerably faster than the deposition of nickel oxide, see Sect. 5.3.1.1. Metal plating elec-... 

Fig. 7.1 Schematic illustrating the template-assisted nanopatteming of conjugated polymers via electrodeposition...

Cherevko S, Xing X, Chung C-H (2011) Hydrogen template assisted electrodeposition of sub-micrometer wires composing honeycomb-like porous Pb films. Appl Surf Sci 257 8054-8061... 

Al-Salman R, Mallet J, Molinari M, Fricoteaux P, Martineau F, Troyon M, Zein El Abedin S, Endres F (2008) Template assisted electrodeposition of germanium and silicon nano wires in an ionic liquid. Phys Chem Chem Phys 10(41) 6233-6237. doi 10.1039/b809075k... 

Al-Sabnan, R. Mallet, J. MoUnari, M. Fricoteaux, R Martineau, F. Troyon, M. El, A., S. Zein Endres, E. Template assisted electrodeposition of germanium and silicon nanowires in an ionic liquid. Phys. Chem. Chem. Phys. 2008,10, 6233-6237. 

Abstract Electrodeposition is a weU-known conventional surface modification method to improve the surface characteristics, decorative and functional, of a wide variety of materials. Now, electrodeposition is emerging as an accepted versatile technique for the preparation of nanomaterials. Work done in this direction is discussed in this chapter. The basics of electrodeposition are introduced, then the electrodeposition of nanomaterials using special techniques for reducing grain size. Methods such as pulse and pulse reverse current deposition, template-assisted deposition and use of additives and grain refiners are explained with suitable examples. Deposition of nanostructured metals, alloys, metal matrix composites, multilayers and biocompatible materials reported in the literature are discussed. Finally, there is a discussion of the improved corrosion resistance of electrodeposited nanostructured materials, quoting results reported in Uterature. 

Template-assisted electrodeposition is another important technique for synthesizing metallic nanomaterials with controlled shape and size. Arrays of nanostmctured materials with specific arrangements can be prepared by this method (Bera et al., 2004 Gurrappa and Binder, 2008). Template synthesis of nanomaterials is reported widely (Fumeaux et al, 1989 Martin, 1994 Hulteen and Martin, 1997 Schonenberger et al., 1997 ElGiar et al, 2000 Tiginyanu et al, 2008 Baranov et al, 2010). 

Schematic electrode arrangement for the synthesis of nanowires through restrictive template-assisted electrodeposition (Beta eta ., 2004). 

Bern D., Kuiry S. C., Patil S. and Seal S. (2003), Palladium nanopaiticle arrays using template-assisted electrodeposition . Applied Physics Letters, 82(18), 3089-91, doi 10.1063/l.1572465. 

In the case of HCOOH electrooxidation, flie Pt mesoporous film with pore diameters between 1.8-2.5 nm and specific surface area of 60 m g showed promising electrocatalytic activity, with a maximum mass specific activity of 8.6 A g obtained for 1 M HCOOH (at 0.38 Vrhe and 333 K) [248]. It must be noted that the liquid crystal templated mesoporous Pt films prepared by Jiang and Kucemak were not investigated in direct CH3OH or HCOOH fuel cells. The reason might be that the mesoporous films were supported on flat Au substrates, which are not suitable as fuel cell electrodes. Bauer et al. developed a technique for non-ionic surfactant-assisted electrodeposition of PtRu on graphite fiber matrix acting as a... 

Surfactants have also been used as a soft template for the electrochemical deposition of mesoporous silica films. Walcarius et al [28] demonstrated the elec-trochemically assisted self-assembly of surfactant-templated silica thm films on various conductive substrates (Au, Pt, glassy carbon, ITO, and Cu). The films were highly ordered and homogeneous over wide areas. Figure 12.10 shows the TEM images of the electrodeposited mesoporous silica films. Hexagonal pores are seen to be well ahgned perpendicular to the surface. It is believed that the cathodic potential applied on the substrate not only drove the sol-gel film... 

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