Electroless plating in synthesizing nickel foams

The technique of low-temperature electroless-plating nickel on the polyurethane foam in synthesizing nickel foams was investigated. The main factors affecting the deposition rate such as temperature, pH value, the concentration of nickle sulfate and reducing agent were explored. The obtained optimum process conditions are 30 g/L NiSO4, 30 g/L NaH2PO2, 10 g/L Na3C6O7H6, 30 g/L NH4Cl, 9.0～9.5 pH value at the reaction temperature of 45 ℃. In this technical condition, the process is stable with the deposition rate of 40 mg/(cm3·h). Nickel foams with a density of 0.74 g·cm-3 and a hole-rate of 91.7% was fabricated by electrodeposition, pyrogenation and deoxidization annealing after the electroless plating.