Densification of Plasma Sprayed SOFC Electrolyte Layer Through Infiltration With Aqueous Nitrate Solution

Abstract

Electrolyte of the solid oxide fuel cells deposited by atmospheric plasma spraying of 8 mol.% yttria (8YSZ), is not applicable in as sprayed condition. Optimization of the plasma spraying process parameters or application of feedstock powder, consisting of 8YSZ and 5wt.% alumina improves the problem of gas leakage through electrolyte layer, whereas provides no solution to the problem of electrodes short-circuiting. Infiltration of deposited electrolyte layer with a thin aqueous solution of nitrate precursors of 8YSZ for one time is a solution to high gas permeability; however three infiltration cycles are required to omit the risk of electrodes short circuiting thoroughly.