Currently there is a strong interest in fabricating nanoporous metal arrays using various template methods. Porous opal membranes of close-packed silica beads, for example, have a unique template structure due to their tetrahedral and octahedral interstices. Such structures can be infiltrated with a variety of materials, especially metals, to form continuous inverse networks. Interest in these forms comes from their potential application in a variety of areas including photonics, magnetics, catalysis, and thermoelectrics. In this paper, we present electron microscopy characterization of inverse nickel photonic materials prepared by electrodeposition method.
Electrodes were formed from opal pieces (typically 7 x 10 x 1.5 mm with silica spheres about 300 nm) by first depositing about 0.5 micron thick copper films on one side of the piece with magnetron sputtering. A length of wire was then attached to the copper backing with silver paste.