Stabilizing nanostructured solid oxide fuel cell cathode with atomic layer deposition.
We demonstrate that the highly active but unstable nanostructured intermediate-temperature solid oxide fuel cell cathode, La0.6Sr0.4CoO3-δ (LSCo), can retain its high oxygen reduction reaction (ORR) activity with exceptional stability for 4000 h at 700 °C by overcoating its surfaces with a conformal layer of nanoscale ZrO2 films through atomic layer deposition (ALD). The benefits from the presence of the nanoscale ALD-ZrO2 overcoats are remarkable: a factor of 19 and 18 reduction in polarization area-specific resistance and degradation rate over the pristine sample, respectively. The unique multifunctionality of the ALD-derived nanoscaled ZrO2 overcoats, that is, possessing porosity for O2 access to LSCo, conducting both electrons and oxide-ions, confining thermal growth of LSCo nanoparticles, and suppressing surface Sr-segregation is deemed the key enabler for the observed stable and active nanostructured cathode.
Department of Mechanical Engineering, University of South Carolina , Columbia, South Carolina 29201, United States.
Yunhui
Y
Gong
Diego
D
Palacio
Xueyan
X
Song
Rajankumar L
RL
Patel
Xinhua
X
Liang
Xuan
X
Zhao
John B
JB
Goodenough
Kevin
K
Huang
D004566:Electrodes; D007477:Ions / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D015040:Zirconium / Q000737:chemistry
D007477:Ions; D010087:Oxides; D015040:Zirconium; C028541:zirconium oxide; D010100:Oxygen