Formation of yttria-stabilized zirconia nanotubes by atomic layer deposition toward efficient solid electrolytes

We describe a fabrication strategy for preparing yttria-stabilized zirconia nanotube (YSZ-NT) arrays embedded in porous alumina membranes by means of template-directed atomic layer deposition (ALD) technique. The individual YSZ-NTs have a high aspect-ratio of well over 120, about ~ 110 nm in diameter, and ~ 14 µm in length. Interfacing the tube arrays with porous Pt was also introduced on the basis of partial etching technique in order to construct Pt/YSZ-NTs/Pt membrane electrode assembly (MEA) structures. The resulting YSZ-NTs MEAs show a 7 mm in diameter with a roughness factor of ~ 2. Area specific resistance was measured up to 1.84 Ω cm² at 400 °C using H₂ as fuel.