8. Nanostructured Electrodes for High-Performing Solid Oxide Fuel Cells

Solid oxide fuel cell (SOFC) is an all-solid-state ceramic electrochemical device for converting chemical energy (fuels) to electricity with high energy efficiency and ultralow harmful emissions. These classes of FCs have received significant attention by researchers as a potential replacement for petroleum-based energy devices. In order to broaden the material selection and increase material system durability, the development of intermediate- or low-temperature SOFC is critical to making their commercialization viable. Therefore, the SOFC performance at lowered operating temperatures must be improved by the innovation of materials and microstructures. The nanostructure engineering of electrodes has demonstrated their improved catalytic performance due to minimization of the electrode polarization resistances for oxygen reduction reaction and fuel oxidation reaction at the nanoscale compared to the traditional electrode design. The synthesis technique strategy was based on wet chemistry catalyst infiltration into electrode structure and has been demonstrated improvements in power density and electrode stability. In this chapter, the technical process of ion infiltration method is discussed; and the different routes in fabricating nanostructured electrodes to achieve high-performing SOFC in hydrogen and hydrocarbon fuels are reviewed. The electrode parameters that lead to improvement of SOFC performance are also summarized. By fabricating electrodes at the nanoscale, a significant increase in specific area was obtained that can provide greater active catalysis sites for electrode reactions, as well as a decrease in the activation polarization resistance which collectively led to improved SOFC performance.