School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798.
Phys Chem Chem Phys. 2011 Sep 7;13(33):15134-42. doi: 10.1039/c1cp20508k. Epub 2011 Jul 25.
The double layer of electrode/electrolyte interfaces plays a fundamental role in determining the performance of solid state electrochemical cells. The double layer capacitance is one of the most-studied descriptors of the double layer. This work examines a case study on lanthanum strontium vanadate (LSV)/yttria-stabilized zirconia (YSZ) interfaces exposed in solid oxide fuel cell anode environment. The apparent double layer capacitance is obtained from impedance spectroscopy. The intrinsic double layer capacitance is evaluated based on Stern's method in conjunction with the Volta potential analysis across LSV/YSZ interfaces. Both the apparent and the intrinsic double layer capacitances exhibit right-skewed volcano patterns, when the interfaces are subjected to anodic biases from 0 to 150 mV. The apparent double layer capacitance is about one order of magnitude larger than the intrinsic double layer capacitance. This discrepancy roots in the inconsistent surface areas that are involved. This analysis of capacitance would provide a more realistic TPB estimate of a working solid-state electrochemical device.
电极/电解质界面的双层在决定固态电化学电池的性能方面起着至关重要的作用。双电层电容是研究双电层的最常用描述符之一。这项工作研究了在固体氧化物燃料电池阳极环境中暴露的镧锶钒酸盐 (LSV)/氧化钇稳定氧化锆 (YSZ) 界面的案例研究。通过阻抗谱获得表观双电层电容。根据 Stern 方法并结合 LSV/YSZ 界面上的 Volta 电势分析，评估了固有双电层电容。当界面受到从 0 到 150 mV 的阳极偏置时，表观双电层电容和固有双电层电容都表现出右偏火山图模式。表观双电层电容比固有双电层电容大约大一个数量级。这种差异源于所涉及的不一致表面积。对电容的这种分析将为工作的固态电化学器件提供更现实的 TPB 估计。
