Nanoporous Anatase Thin Films as Fast Proton‐Conducting Materials

Nanoporous anatase thin films (see Figure) have been prepared via particulate sol–gel processes. The proton conductivity shows a sigmoidal dependence on relative humidity (RH). The highest value of proton conductivity was 3.78 × 10–2 S cm–1 at 80 °C and 81% RH. The comparable proton conductivity, lower cost, and higher hydrophilicity of these thin films make them potential substitutes for Nafion membranes in proton-exchange membrane fuel cells.