Gold three dimensional film electrode prepared from oppositely charged nanoparticles

Nanoparticulate gold film electrodes were prepared from oppositely charged gold nanoparticles (c.a. 6 nm diameter) by a layer-by-layer approach without application of linker molecules. This was done by alternative immersion of indium tin oxide plates into suspensions of positively and negatively charged particles. The thickness of the film and the magnitude of the characteristic surface plasmon band are proportional to the number of immersion and withdrawal steps. Up to nine double immersions and withdrawal steps can be used to systematically increase the amount of nanoparticulate gold material. The capacitive current density and current density of hydrogen peroxide reduction are proportional to the number of immersion and withdrawal steps. Highly efficient and low overpotential glucose electrooxidation in alkaline solution is demonstrated.