Pd–Co₃O₄/acetylene black nanocomposite as an efficient and robust bifunctional ORR/OER electrocatalyst for rechargeable zinc-air batteries

• Published in: International journal of hydrogen energy 2024-11, Vol.91, p.1103-1112
• Main Authors: Akbarian, Parisa, Eshghi, Abolfath, Asadi, Aliakbar, Kheirmand, Mehdi
• Format: Article
• Language: English
• Subjects: Bifunctional electrocatalyst; Co₃O; Metal-air battery; Oxygem reduction reaction; Oxygen evolution reaction; Palladium
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2024.10.225

Developing cost-effective and high-performing bifunctional electrocatalysts is pivotal for advancing rechargeable zinc-air batteries (ZABs). In this study, a Pd–Co₃O₄ loaded on acetylene black (Pd–Co₃O₄/C) electrocatalyst was developed with excellent properties for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) using reduced H₂PdCl₄ to modify Co₃O₄/C. The experimental findings indicate that the Pd–Co₃O₄/C electrocatalyst exhibits a favorable half-wave potential for ORR at 0.91 V, a feasible potential for OER at 1.48 V (measured at 10 mA/cm2), also minor Tafel slopes for both ORR (44.65 mV/dec) and OER (58.41 mV/dec). Additionally, it evidences a power density of 186 mW/cm2 in ZABs and good durability during galvanostatic charge-discharge cycling. The impressive performance of Pd–Co₃O₄/C can be ascribed primarily to the beneficial synergistic effect resulting from the composition of Co₃O₄ and Pd embedded within graphite carbon. This research lays the groundwork for the expansion of additional cost-effective and highly effective electrocatalysts in the coming years. [Display omitted] •Pd-Co₃O₄/C as a bifunctional oxygen electrocatalyst was developed.•Pd-Co₃O₄/C achieves 1.02 V onset potential vs. RHE and 290 mV overpotential at 10 mA/cm² current density.•Pd-Co₃O₄/C shows exceptional cyclic stability at high current density due to high electron transfer and synergistic effects.