Macroporous silicon hydrogen diffusion layers for micro-fuel cells: From planar to 3D structures

► Use of macroporous silicon as a hydrogen diffusion layer in integrated planar proton exchange membrane micro-fuel cells. ► Fuel cell active surface enhanced applying electrochemical etching process to 3D corrugated-like silicon substrates. ► 8 ccm/cm2 H2 flow rate through the planar porous substrates with an incoming pressure of 5 mbars and four time higher in the case of 3D membranes. ► Power densities up to 250 mW/cm2 for planar micro fuel cells.