A robust tubular solid oxide fuel cell through bifunctional praseodymium oxide nanocatalyst infiltration

Abstract

Due to inherent merits such as rapid start-up, easy sealing, and good thermal cycling resistance, tubular solid oxide fuel cell (SOFC) is becoming a promising alternative device for clean and efficient energy conversion; yet the lower power density is a challenging problem when compared to planar SOFC. In this study, an asymmetric infiltration of Pr6O11 nanocatalyst, a bi-functional catalyst, is innovatively proposed to enhance the electrochemical performance and prolong the cell lifespan. First, a suitable anode functional layer (AFL) based on the Ni-YSZ (yttria stabilized zirconia) anode is presented. The additional AFL results in a significantly enhanced peak power density (PPD) of 1259 mWcm−2 at 800 °C, which is 66 % higher than that of the primitive cell (756 mWcm−2). Subsequently, a new approach of asymmetric infiltration is devised in one step during the cell manufacturing procedure to simultaneously modify the anode and cathode-electrolyte interface to boost cell output power. Consequently, the nanostructure-engineered tubular cell exhibits outstanding peak power density of 1592 mWcm−2 at 800 °C, that is more than twice that of the blank cell, outperforms the majority of the Ni-YSZ supported tubular cells. Furthermore, the robust tubular cell runs on hydrogen fuels with excellent stability over more than 2000 h at a constant current density of ∼300 mAcm−2. The exceptional performance and endurance can be attributed to the rational cell design, which holds great potential for the commercialization of tubular SOFC.