Fabrication of nanostructured Pt electrodes templated by nanoporous anodic alumina for electrochemical sensors

Although platinum electrodes are widely used in electrochemical sensors their functionality can be affected by formed components of complex biological fluids. We demonstrated a simple approach to the formation of Pt nanopillars sandwiched between W metal layers and nanoporous anodic alumina membranes, by anodization of W/Al bilayers and substitution of WO3 nanopillars formed by the local anodization of W under the nanopores with Pt. By exploiting the Pourbaix corrosion diagram of W, we could find conditions that allow the selective dissolution of WO3 in pH = 7.4 buffer solution and formation of Pt nanopillars inside the nanoporous aluminum membrane via electroless deposition.