Tailored Double Perovskite with Boosted Oxygen Reduction Kinetics and CO<sub>2</sub> Durability for Solid Oxide Fuel Cells
Sigeng Chen, Haixia Zhang, Chuangang Yao, Tingting Qu, Tan Wang, Haocong Wang, Wanning Liu, Xiaoshi Lang, Kedi Cai
Abstract
The issues related to the oxygen reduction efficiency and CO 2 endurance pose challenges to achieving efficient electrochemical energy conversion in solid oxide fuel cells. Here, we develop an effective strategy using only Cu doping to boost the oxygen reduction kinetics and CO 2 durability of NdBa 0.5 Sr 0.5 Co 2 O 5+δ (NBSC). By introducing Cu ions into the Co sites of the NdBa 0.5 Sr 0.5 Co 2 O 5+δ (NBSC) lattice, the concentration of oxygen vacancies as well as the ratio of Co 3+ /Co 4+ can be effectively controlled. Consequently, the charge transfer and oxygen dissociation during the ORR process, as well as the average bonding energy, are significantly tuned, leading to the simultaneous enhancement of ORR catalytic activity and CO 2 tolerance. Typically, NdBa 0.5 Sr 0.5 Co 1.8 Cu 0.2 O 5+δ (NBSCC0.2) displays a R p of 0.04 Ω cm 2 and a PPD of 1.03 W cm –2 at 750 °C. This work provides a highly effective way to develop materials for next-generation energy conversion devices.