多孔电解质过渡层对阴极材料电化学性能的影响

The Effect of Porous Electrolyte Interlayer on the Electrochemical Performance of Cathode Materials

通过丝网印刷法在致密Ce_(0.8)Sm_(0.2)O_(1.9)(SDC)电解质和LaBaCo_2O_(5+δ)(LBCO)阴极之间制备了一层多孔SDC电解质过渡层,并研究了此过渡层对阴极在中温范围内的电化学性能的影响。实验表明LBCO阴极在经过多孔结构的SDC过渡层修饰后表现出更低的面积比电阻和极化过电位,具有更高的电化学性能。经过SDC过渡层修饰的LBCO阴极在800℃时的面积比电阻约为0.027Ωcm^2,比同样条件下未经过SDC过渡层修饰的LBCO阴极下降了约4/5,在700℃,电流密度为0.2Acm^(-2)时的极化过电位同样降低了约65.7%。在阴极和致密电解质之间经过一薄层多孔电解质的修饰能够显著地提高阴极材料在中温范围内的电化学性能。

An interlayer of porous SDC electrolyte is prepared by screen-printing method between dense Ce0.8Sm0.2O1.9（SDC） electrolyte and LaBaCo2O5＋δ（LBCO） cathode. The effect of the porous SDC interlayer on the electrochemical performance of LBCO cathode in the moderate temperature range is investigated. Experimental results show that the LBCO cathode with porous SDC interlayer exhibits much lower area-spe- cific resistance and polarization overpotential and better electrochemical performance. For LBCO cathode with porous SDC interlayer, the ASR is 0.0271-1cm^2 at 800℃, about four-fifths lower than that of the LBCO cathode without porous SDC interlayer under the same condition, and the cathodic overpotential is reduced by 65.7 % at a current density of 0.20 Acm^-2 at 700℃. The application of a thin-layer of porous electrolyte between cathode and dense electrolyte can greatly improve the electrochemical performance of cathode materials for at intermediate temperature.