Nanoporous silicon membrane for fuel cells realized by electrochemical etching

In this work we propose a simple method to realize nanoporous silicon proton exchange membranes for fuel cells. The electrochemical etching allows in a single step, the grooving of the membrane and the realization of double porous silicon (PS) layer. We have studied the impact of the different electrochemical conditions: current density, the electrolyte concentration (ethanoic HF) and the anodization time leading to optimal thickness (of 50–90 μm) and nanoporosity for silicon microstructures. The experimental techniques employed for surface studies and depths of groove in silicon are mainly scanning electronic microscopy (SEM) and atomic force microscopy (AFM) which give information of the silicon microstructures. Photoluminescence (PL) measurements of porous silicon membrane were carried out in order to investigate the optical properties of the PS.