Preparation of microporous nickel electrodeposits using a polymer matrix

Nickel-mesh electrodes were embedded into polyHIPE (a generic hollow fiber polymer) by immersion in the precursor emulsion and subsequent entrapment i nto the solid microporous matrix produced by polymerization and drying. Imm ersing this Ni/polyHIPE/Ni composite into a nickel electroplating bath and passing direct current through the two electrodes resulted in growing Ni el ectrodeposits on the cathode and through the polymer cells and pores. When the polymer matrix was subsequently burned off, a granular microporous Ni c oating was produced on the cathode. Variation of the electroplating time an d current density showed that the structure of the Ni coating is determined by the local distortions of the electric field inside the tortuous micropo rous body of the insulating polymer. (C) 1999 Elsevier Science Ltd.