With no Color and Scent (part III): Architecture of metal shells grown   on templates by pulse current electrodeposition
  A method of growing mushroom or shell like nanostructured metal convex concave models has been worked out. Silver,copper,nickel,rhodium and Pd-Ni,Pd-Co alloy structures are reproduced as a result of self-assembly of nanowires growing on porous membranes in the course of pulse current electrodeposition. It is shown that the method allows to model not only the shell shape but also the hierarchical structure at the nano, micro and mesolevels. A 1,2 mm sized shell was grown from Pd-Ni alloy. The architecture of the models was studied by fragmentation and chemical etching. The images were obtained using SUPRA 50 VP and JEOL scanning electron microscopes. The metal shell is a bowl-shaped frame, its walls composed of densely packed nanoelements. Each nanoelement is a conical bundle of nanowires grown as a supported wine glass. The shell inner surface is a weave of nanowires with a vegetation pattern with bottom up directed lines. The inner surface exhibits also well pronounced transverse rings formed by the bottom up growing bundles of nanowires that compose the shell frame. A number of nanowire bundle ends rise to the shell outer surface as nanoflowers that can serve as templates for growing nanowires. In some cases the nanowires growing on the outer surface form a copy of plate mushroom. A hypothesis is proposed that pulsed growth on membranes is a tool of morphogenesis of many mushrooms and plants. 
Galina Strukova, Gennady Strukov, Sergey Egorov
cond-mat.mtrl-sci physics.chem-ph