Novel core–shell structure of perovskite anode and characterization

Abstract

The core–shell anode particulates are prepared with perovskite core of (Sr0.7La0.3)(Ti1−xNbx)O3 and the shell of multiple elements doped solid electrolyte (La0.75Sr0.2Ba0.05)0.175Ce0.825O1.891 (LSBC) by a citric acid-based combustion (SV) coating process. The ionic shell LSBC precedes the peak reduction–oxidation reaction temperature of the anode to 500 °C. The selected coverage ratio of 1.5 or 3.0 mol% LSBC shell on the core is used to ensure appropriate electrocatalytic activity and electronic conductivity. The core–shell anode increases the interface charge transfer (ReZ(i)) and chemical catalysis (ReZ(c)) that is revealed on the reduction of AC impedance. The lower slope of the voltage drop for the half-cell, which is composed of the core–shell anode, indicates the increasing effective triple phase boundary (TPB) sites and reduces the interface thermal expansion and lattice matching, as well as extends the ionic conduction path from LSBC electrolyte to the core–shell anode. The power density increases three times by using the core–shell structural anode than without using the core–shell anode in the half-cell.