Mesoporous MXene boosts iron-based catalyst for efficient oxygen reduction in zinc-air batteries

 The oxygen reduction reaction (ORR) is a critical process in energy conversion devices such as fuel cells and metal-air batteries. However, its slow kinetics often require the use of efficient catalysts. While platinum-based catalysts are highly active, their high cost and limited stability hinder widespread use. Iron phthalocyanine (FePc), with its unique FeN₄ structure, has shown promise as a non-noble metal alternative, but it suffers from poor conductivity and a tendency to aggregate.  

       To overcome these limitations, researchers from Donghua University developed a composite material by loading FePc onto mesoporous Ti₃C₂ MXene (Meso-Ti₃C₂) through a simple ultrasonic liquid-phase method. The Meso-Ti₃C₂ support features abundant in-plane pores and edge sites, which help optimize the electronic structure of the FeN₄ centers, enhance mass transfer, and improve the accessibility of active sites. As a result, the FePc/Meso-Ti₃C₂ catalyst exhibits outstanding ORR performance in alkaline media, with a half-wave potential of 0.914 V (vs. RHE) and a Tafel slope of 57.2 mV/dec—surpassing both conventional FePc/Ti₃C₂ and commercial 20% Pt/C catalysts. When applied in a zinc-air battery, it achieved a peak power density of 183.1 mW/cm² and demonstrated excellent long-term stability.  

        This study not only provides a highly efficient and stable cathode catalyst for metal-air batteries but also introduces a general mesopore-engineering strategy to enhance the performance of molecular electrocatalysts. The work titled “Mesoporous Ti₃C₂-loaded iron phthalocyanine (FePc) electrocatalyst for efficient oxygen reduction reaction under alkaline conditions” was published in the Journal of Donghua University (English Edition) (published online in 2025).