Boosting and Robust Multifunction Cathode Layer for Solid Oxide Fuel Cells

Abstract

Designing an efficient cathode and an accelerating sluggish oxygen reduction reaction (ORR) process are crucial to enhancing electrochemical outputs for solid oxide fuel cells (SOFCs). A novel multifunction layer (MFL) cathode that combines the Gd 0.2 Ce 0.8 O 2−δ (GDC) interlayer with a La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ (LSCF) cathode functional layer is reported. After precisely controlling the concentration of an infiltration precursor solution, discrete and filmy LSCF on the GDC scaffold (MFL-D and MFL-F) can be prepared. Compared with the discrete-coating of LSCF (MFL-D), the film-like coating of LSCF (MFL-F) exhibits a lower initial polarization impedance of 0.093 Ω cm 2 at 750 °C. The as-obtained SOFCs produce an enhanced peak power density of 0.93 W cm −2 and have successfully been operated at 0.5 A cm −2 for 400 h with a voltage degradation of only 16 mV. Oxygen ion transport model of the MFL-F is constructed and discussed. This work provides an important insight into designing efficient cathode for SOFCs.

Overview of Approaches to Increase the Electrochemical Activity of Conventional Perovskite Air Electrodes

“…The effective approach to increase the electrochemical activity of the conventional perovskite electrodes by increasing the TPB is related to the preparation of decorated electrodes by the infiltration (also called impregnation) method, where the porous cathode is filled with various additives [148,163,304,323,340,382,403,[434][435][436][437][438] as well as decorating the electrode surface with nanocatalysts [141,154,315,387,405,416,426,439] and nanocoatings [303,308,341,342], which significantly improve the electrode surface diffusion and exchange with the gas phase.…”

Highly Efficient and Stable Intermediate-Temperature Solid Oxide Fuel Cells Using PrCo0.5Ni0.5O3−δ Cathode

“…Since solid oxide fuel cell (SOFC) can efficiently convert chemical energy into electricity with features of good fuel flexibility and environmentally friendly, it has been widely studied by scholars. − However, the slow rate of oxygen reduction reaction (ORR) on the cathode side of SOFC at intermediate or low temperatures (≤800 °C) would lead to shorten the fuel cell life span and reduce the output performance, making it difficult to achieve large-scale commercial application. − Therefore, priority research on cathode materials at intermediated/low-temperature ranges is particularly important for the development of SOFC. − …”

Boosting Performance of a Protonic Ceramic Fuel Cell by the Incorporation of Active Nano-Structured Layers

“…Nevertheless, the active reaction zones are confined to the two-dimensional reactant gas–cathode–electrolyte TPBs . Numerous strategies have been proposed to improve the performance of the cathode by extending the TPB for oxygen reduction reaction (ORR): (1) the electrode material and electrolyte are combined to form a composite cathode; (2) the infiltration technique has been regarded as a facile route to prepare highly active electrodes for improving PCFC performance; and (3) the nano-structured active layer (NAL) between the porous electrode and the dense electrolyte are incorporated. ,− …”