Strukovˆà Gennadyˆà V.,ˆà Strukovaˆà Galina K.

E-mail: strukova@issp.ac.ru

Metallicˆà nanostructured mesostructures are formed as a result of their self-assembly while growing of nanoclusters and nanowires during the pulsed current electrodeposition process on the membranes.

Our work shows that the pulsed current electrodeposition on the templates is a general biomimetic method to fabrication of metal models of natural objects: protozoa, plants, mushrooms, shells. The resulting metal copy reproduce the Benoit Mandelbrot classic natural fractals.

Pd-Ni alloy

		We have shown the possibility to control mold shapes and found the conditions ensuring fabrication of a single type of shell-like convex-concave structures.

The inner surface of shellˆà is a picture ofˆà theˆà metallic electrospun,ˆà can beˆà seen theˆà grid lines of growthˆà as òÀÜmeridiansòÀÝ and òÀÜparallelsòÀÝ

The outer surface is formed by either òÀÜnanoflowers" or nanowires. In this case, the outer surface of the shell looks like a brush

Hypothesisˆàof morphogenesis:

We assume that pulsed growth on the membranes is a morphogenesisòÀÙ tool for mostˆà plants, mushrooms and shells

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Nature
Pd-Ni

We can definitely identify common features in the growth of mushrooms and plants and their metal models:

òÀâThe growth on theˆà membranes or templates

òÀâGrowth process is exercisedˆà by the accession of the materialˆà atˆà different points of growth. The location of these points affectsˆà the shape and causes a fractal branching

òÀâThe nature of the growth process is uneven or pulsed

òÀâThis pulsed growth is accompanied by a fractal branching and self-assembly of growing clusters (fibers) and provides a hierarchical structure

The alternating electrodeposition of PbIn and PdNi alloysˆà allowedˆàˆà to obtain a hybridˆàˆàˆà volumeˆà structure òÀÜfernòÀÝ. Arrow-like leaves formed by four orthogonal blades are situated along the stem; the blades consist in their turn of alternating submicron columns, which consist of spherical granules of 100-200ˆà nm.

The alternating electrodeposition ofˆà Pb and PdNi alloysˆà hollow metal structureˆà òÀÜsedumòÀÝ

The nanostructured mesostructures of the magnetic (Ni, Pd-Ni, Pd-Co), superconducting (Bi, Pb, Pb-In) and normal (Ag, Rh, Pd, Au, Cu) metalsˆà were obtained.

It is shown that our technique enables to reproduce no only the exterior shell form but also the hierarchic layer shell structure at the nano-and microscale.

Fragments of the shalls		The layered structure of the shell	Fragments of the shell hierarchical structure

Nanowiresˆà are material forˆà architectural buildingˆà blocks	Layeredˆà packing of structural fragments

Etching of the shell surface

Before etching	After etching		Nanoscopic cells of the shell skeleton
The nanostructured mesostructures of the magnetic, superconducting and normal metalsˆà were obtained. This gives prospects for fabrication of useful "hybrid" structures andˆà nanodevices. Such objects can be of interest for fundamental research of self- assembly processes as well as for applications in catalysis, electronics, optics, medicine, and for fabrication of superhydrophobic surfaces.

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