The metallisation of insulating substrates with nano-structured metal films of controllable pore dimension†
By use of Photocatalytically Initiated Electroless Deposition (PIED) we have deposited nanoporous metal films with both single and multi-layer, highly ordered arrays of sub-μm spherical pores directly onto the surface of insulating substrates. This has been achieved by sensitisation of the target substrate with a TiO2 photocatalyst followed by the self-assembly of a hexagonally close packed polystyrene microsphere template, assisted by the photogenerated hydrophilicity of the TiO2 sensitiser. Metal is then deposited through PIED into the interstitial spaces of a template and directly onto the TiO2 sensitised substrate surface. The dimensions of the resultant pores in the deposited metal are determined by the size of the microspheres used to for the template while metal film thickness may be controlled by the deposition period.