Electroless copper plating Catalytic

Presuming the electrochemical mechanism electroless copper plating [19], namely, the catalytic reduction of Cu(II) ions by formaldehyde, the partial reactions occurring at equal rates under open-circuit conditions could be written (using the deuterium tracer to specify the origin of hydrogen) in a simplified form as follows ... 

Because of the high conductivity of copper, electroless copper plating is currently used to manufacture conductive fabrics. Electroless copper plating on fabrics has been studied by some researchers [1-6]. Electroless metal plating is a non electrolytic method of deposition from solution [7]. The electroless deposition method uses a catalytic redox reaction between metal ions and dissolved reduction agent[8-12]. This technique advantages, such as low cost, excellent conductivity, shielding effectiveness... 

The final process step is a chemical plating of "catalytic" resin sites with electroless copper/nickel/tin etc. 

Electroless plating — An autocatalytic process of metal deposition on a substrate by reduction of metal ions from solution without using an external source of electrons. It is promoted by specific reductants, namely formaldehyde, sodium hypophosphide, sodium boro-hydride, dialkylamine borane, and hydrazine. Electroless deposition has been used to produce different metal (e.g., nickel, cobalt, copper, gold, platinum, palladium, silver) and alloy coatings. It can be applied to any type of substrate including non-conductors. Some substrates are intrinsic catalytic for the electroless deposition other can be catalyzed usually by sensibilization followed by Pd nucleation also, in some non-catalytic metallic substrates the electroless process can be induced by an initial application of an appropriate potential pulse. In practical terms, the evaluation of the catalytic activity of a substrate for the electroless deposition of a given metal is... 

C. Fukuhara, Y. Kamata, A. Igarashi, Catalytic performance of microtube-type copper-based catalyst for methanol steam reforming, prepared on the inner wall of an aluminum tube by electroless plating, Appl. Catal. A-Gen. 296 (2005) 100. 

Formaldehyde oxidation rate in electroless plating solution is also higher compared to Cu(II)-free formaldehyde solution. In this case, a nonadditive could be equally explained by the higher catalytic activity of freshly deposited copper metal. 

Electroless plating baths have been developed for copper, diver, nickel, and other plating elements, but the nickel/phosphorus system is the most common for wear resistance. The deposit is achieved by a catalytic reduction of metal ions in the plating without the use of electricity. 

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