Fabrication of low-temperature solid oxide fuel cells with a nanothin protective layer by atomic layer deposition

Abstract

Anode aluminum oxide-supported thin-film fuel cells having a sub-500-nm-thick bilayered electrolyte comprising a gadolinium-doped ceria (GDC) layer and an yttria-stabilized zirconia (YSZ) layer were fabricated and electrochemically characterized in order to investigate the effect of the YSZ protective layer. The highly dense and thin YSZ layer acted as a blockage against electron and oxygen permeation between the anode and GDC electrolyte. Dense GDC and YSZ thin films were fabricated using radio frequency sputtering and atomic layer deposition techniques, respectively. The resulting bilayered thin-film fuel cell generated a significantly higher open circuit voltage of approximately 1.07 V compared with a thin-film fuel cell with a single-layered GDC electrolyte (approximately 0.3 V).

Engineering of the electrode structure of thin film solid oxide fuel cells

“…Many studies to lower the electrolyte resistance of SOFCs have been conducted by exploring alternative electrolyte materials and by developing cell structures with thin film technologies [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24]. Recently, ceria-based electrolyte materials have received attention due to their high ionic conductivity and reactivity at lower temperatures.…”

“…Recently, ceria-based electrolyte materials have received attention due to their high ionic conductivity and reactivity at lower temperatures. However, their chemical instability under SOFC operation conditions imposed the practical difficulties for wider applications [6][7][8]. Thus, traditional zirconia-based electrolyte materials remain attractive due to their greater chemical stability and long-term reliability.…”

“…In consideration of the thermomechanical stability, nanoporous templates have been suggested as substrates to support thin film fuel cells for their high reliability as well as efficient gas delivery [8,[16][17][18][19]. It has been demonstrated that in cases where thin films were supported by nanoporous anodic aluminum oxide (AAO), their electrical and microstructural degradation could be significantly mitigated even at elevated temperatures [20].…”

“…Extensive efforts, therefore, have been devoted to producing defect-free electrolyte layers with a sub-micrometer thickness on the AAO substrates. Some groups demonstrated the fabrication of the thin film SOFCs on the porous substrates without gas leakage, with the assistance of bi-layered electrolytes and modified electrolytes [8,21,22].…”

Amorphous to Tetragonal Zirconia Nanostructures and Evolution of Valence and Core Regions

“…This shoulder is attributed to metallic zirconium with Zr +ζ , |ζ| < 4. 26 Reduced zirconium combined partially with the oxidant during the ALD process. 26 The Journal of Physical Chemistry C Article 3d 3/2 .…”