Molecular Iron Oxide Clusters Boost the Oxygen Reduction Reaction of Platinum Electrocatalysts at Near‐Neutral pH

Abstract

The oxygen reduction reaction (ORR) is a key energy conversion process, which is critical for the efficient operation of fuel cells and metal-air batteries. Here, we report the significant enhancement of the ORR-performance of commercial platinum-on-carbon electrocatalysts when operated in aqueous electrolyte solutions (pH 5.6), containing the polyoxoanion [Fe 28 (μ 3 -O) 8 (L-(À )-tart) 16 (CH 3 COO) 24 ] 20À . Mechanistic studies provide initial insights into the performance-improving role of the iron oxide cluster during ORR. Technological deployment of the system is demonstrated by incorporation into a direct formate microfluidic fuel cell (DFMFC), where major performance increases are observed when compared with reference electrolytes. The study provides the first examples of iron oxide clusters in electrochemical energy conversion and storage.

Cobalt–Copper-Embedded Nitrogen-Doped Carbon Nanostructures Derived from Zeolite Imidazolate Frameworks as Electrocatalysts for the Oxygen Reduction Reaction

“…The demand for sustainable energy solutions continues to increase with increasing fossil fuel consumption. , Therefore, advanced research on energy generation and utilization technologies is crucial for a safe and sustainable future. − The electrocatalytic oxygen reduction reaction (ORR) is essential for energy conversion and storage in devices such as fuel cells and metal-air batteries. − Despite the widespread use of Pt-based catalysts, their high cost, limited durability, and low methanol tolerance require the development of optimal materials for ORR catalysts. − Hence, researchers have focused on the development of carbon-based ORR catalysts with high ORR catalytic activity as alternatives to Pt. Nanostructures based on graphene or oxidized graphene and carbon-based catalysts doped with heteroatoms are at the forefront of this research effort.…”

“… 5 − 16 Despite the widespread use of Pt-based catalysts, their high cost, limited durability, and low methanol tolerance require the development of optimal materials for ORR catalysts. 15 − 17 Hence, researchers have focused on the development of carbon-based ORR catalysts with high ORR catalytic activity as alternatives to Pt. Nanostructures based on graphene 18 or oxidized graphene 19 and carbon-based catalysts doped with heteroatoms 20 are at the forefront of this research effort.…”