Effects of interlayer thickness on the electrochemical and mechanical properties of bi-layer cathodes for solid oxide fuel cells

A hybrid method that combines an interlayer prepared by a pulsed laser deposition (PLD) technique and a conventional cathode prepared by a screen printing method is employed to fabricate bi-layer La _0.5Sr _0.5CoO _3-δ (LSCO) cathodes. Robust bi-layer cathode films are successfully fabricated with a porous microstructure and excellent integrity with the underlying electrolyte layer. By adjusting the thickness of the PLD interlayers from ∼50 to ∼500 nm, a systematic variation of the electrochemical and mechanical properties of the bi-layer cathodes is observed. Compared with single cells without an interlayer, the anode-supported single cells with an LSCO interlayer thickness of ∼100 nm exhibit significant enhancement in the overall power performance.