Synthesis electroless deposition technique

The design of the interstices filling in colloidal crystals with appropriate media and subsequently fluid-solid transformation is central to the whole synthesis. Fluid precursors in the voids of crystal arrays can solidify by polymerization and sol-gel hydrolysis. More recently, many methods have been developed including salt precipitation and chemical conversion, chemical vapor deposition (CVD), spraying techniques (spray pyrolysis, ion spraying, and laser spraying), nanocrystal deposition and sintering, oxide and salt reduction, electrodeposition, and electroless deposition. 

A BCP is a good tool for the design of nanostractured materials, as discussed in the previous sections. It offers a flexible platform for a variety of nanomaterials with functionalities and robustness since one can combine BCP SA with a sol-gel process, nanoparticle synthesis, chemical vapor deposition, electrodeposition, or electroless deposition. Thus, in principle, the structural and material diversity obtained from the aforementioned techniques is substantial. This section introduces specific classes of material prepared from BCP-directed SA by the Wiesner group. 

The Electroless Plating technique (EPD) [5] was used to obtain dense Pd layers on various PSS substrates. From the characterization results obtained for modified PSS supports, two of them were set as substrates for the synthesis of Pd composite membranes by EPD. The first support was obtained after oxidation at 700°C for 12h and the second one was obtained by coating a thin layer of Zr02. The PSS substrates were activated prior to Pd deposition. The activation process was performed using sequential dipping in SnCl2-HCl (1 g/1, pH 2) and PdC -HCl (0.1 g/1, pH 2) solutions. 

A typical catalyst layer preparation for a functional PEMFC cell is illustrated in Fig. 6. There are several other techniques for catalyst synthesis which includes electro- and electroless deposition, sol-gel and sputtering. 

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