A Highly Efficient Co₃O₄ Nanoparticle‐Incorporated Mesoporous Beta Composite as a Synergistic Catalyst for Oxygen Reduction

Abstract

Abstract Cost‐efficient and high‐performance oxygen reduction electrocatalysts are widely pursued to boost the sluggish oxygen reduction reaction (ORR) for renewable‐energy technology applications. Here, a novel precious‐metal‐free cathode catalyst, Co 3 O 4 nanoparticle‐incorporated mesoporous Beta zeolite, was first synthesized by using a facile steam‐assisted crystallization (SAC) and hydrothermal approach. Owning to the synergetic catalytic effects between the Co 3 O 4 nanoparticles and the mesoporous Beta matrix, the resulting Co 3 O 4 / m ‐Beta nanocomposites catalyst showed comparable ORR electrochemical catalytic activity to the benchmark 20 wt% Pt/C catalyst with a high onset potential of 0.88 V, and much higher methanol tolerance with a negligible negative shift of the peak potential and excellent electrochemical stability in alkaline media. The relatively higher surface Co 2+ concentration and the abundant Brønsted acid sites facilitate the ORR process, mainly through a 4e − pathway, which makes the Co 3 O 4 / m ‐Beta nanocomposite a favorable candidate for improving energy storage and conversion efficiencies in fuel cells.