Molybdenum-Pocket Driven Low-Platinum Oxygen Reduction Catalysts for 100-Watt-Scale Fuel Cell Stacks.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 42157682.
- Also identified by DOI 10.1002/adma.73444.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Developing highly efficient and low-platinum (Pt) proton exchange membrane fuel cell (PEMFC) stacks is imperative for their commercialization. However, ultralow-loading Pt catalysts (<0.10 mg cm<sup>-2</sup>) are inherently less active and unstable due to high oxygen resistance, particularly under practical stack operating conditions. Here, we present a molybdenum oxide-pocket-driven Pt<sub>2</sub>Co (MoO<sub>3</sub>-Pt<sub>2</sub>Co) alloy to tackle the aforementioned challenge, where MoO<sub>3</sub> with abundant oxygen vacancies can act as the pivotal "oxygen storage pocket" to boost the oxygen reduction reaction (ORR) activity and minimize the leaching of Co. Consequently, the MoO<sub>3</sub>-Pt<sub>2</sub>Co/C-based membrane electrode assembly (MEA) enables exceptional peak power densities of 3.20 W cm<sup>-2</sup> and 1.73 W cm<sup>-2</sup> in H<sub>2</sub>-O<sub>2</sub> and H<sub>2</sub>-air, respectively, with a low Pt loading of 0.10 mg cm<sup>-2</sup>, outperforming cutting-edge MEAs. Meanwhile, the MoO<sub>3</sub>-Pt<sub>2</sub>Co/C-based MEA can retain a record-breaking mass activity of 1.68 A mg<sup>-1</sup> after 30k-cycle accelerated stress tests and can be operated stably at 0.65 V beyond 550 h. Most importantly, we develop a MoO<sub>3</sub>-Pt<sub>2</sub>Co/C-based fuel cell stack that delivers an excellent rated power of 123 W in H<sub>2</sub>-air, which can project Pt utilization of 0.0975 g<sub>Pt</sub> kW<sup>-1</sup> for a 100-kW hydrogen fuel cell vehicle, exceeding the US Department of energy (DOE) ultimate target of 0.10 g<sub>Pt</sub> kW<sup>-1</sup>.