Highly Porous Gold Electrodes - Preparation and Characterization

Gold screen printed electrodes (Au-SPEs) were treated electrochemically to produce a micro-rough pattern increasing the real electrode surface. The procedure based on the Dynamic Hydrogen Bubble Template (DHBT) method included electrochemical deposition of Au layers onto the surface of the Au-SPEs, followed by a reductive process at -3 V (vs. Ag/AgCl) leading to formation of H-2 bubbles, which produced pores in the Au multilayer. The morphology of the micro-porous Au electrode was characterized by scanning electron microscopy (SEM), surface mapping, surface profilometry, and confocal microscopy. The electrode surface morphology was controlled by the time of the electrode reductive treatment (H-2 evolution) and the optimized condition resulting in the best surface structuring was found. Notably, the surface roughness leading to the highest electrode surface area was significantly increased compared to previously reported results with Au-SPEs.