Spinel CoFe2O4/carbon nanotube composites as efficient bifunctional electrocatalysts for oxygen reduction and oxygen evolution reaction

In the development of fuel cells, it is the key to large-scale commercialization of fuel cells to rationally design and synthesize efficient and non-noble metals-based bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In this paper, spinel CoFe2O4/carbon nanotube composites (CoFe2O4/CNTs/FA) were synthesized by solvothermal and calcination method. XRD, TEM, XPS and BET characterizations indicate that the addition of complexing agent fumaric acid can improve the crystal growth kinetics and morphology of CoFe2O4/CNTs nanohybirds. The as-synthesized CoFe2O4/CNTs/FA pyrolyzed at 500 degrees C have an outstanding bifunctional catalytic activity for ORR and OER with the potential of 1.62V (vs. RHE) at a current density of 10 mA/cm(2) and half-wave potential E-1/2 = 0.808V (vs. RHE) in alkaline electrolyte, respectively. It is obviously better than unloaded CoFe2O4 nanoparticles and commercial CNTs. CoFe2O4/CNTs/ FA also exhibit better methanol tolerance ability and durability than commercial Pt/C and RuO2 catalyst. This investigation broadens an idea of simple compounding of spinel with carbon-based materials to improve electrochemical properties.

Automated summary

The study focuses on designing and synthesizing efficient catalysts for fuel cells, demonstrating that CoFe2O4/CNTs/FA composites have excellent bifunctional catalytic activity for ORR and OER with improved methanol tolerance and durability compared to standard catalysts like Pt/C and RuO2. This shows potential for simple compound strategies to enhance electrochemical properties.