Microenvironment Tailoring of NiCo Alloys Coupled with FePc as Efficient Bifunctional Catalysts for High-Rate Zn-Air Batteries

• Published in: Langmuir 2024-08, Vol.40 (32), p.17038-17048
• Main Authors: Chen, Xiaorong, Yue, Dandan, Yu, Xinmeng, Chen, Yazhu, Chen, Xiaoting, Wang, Hongqiang, Li, Qingyu, Ma, Zhaoling
• Format: Article
• Language: English
• ISSN: 0743-7463; 1520-5827; 1520-5827
• DOI: 10.1021/acs.langmuir.4c02023

The practical application of Zn-air batteries require exploring cost-effective and durable bifunctional electrocatalysts. However, the simultaneous preparation of catalysts with bifunctional activities for oxygen reduction reaction (ORR) and oxygen precipitation reaction (OER) remains challenging. Herein, we synthesized a novel hybrid catalyst (FePc/NiCo/CNT), which couples NiCo alloy with FePc through electrostatic interaction. The interaction between FePc and NiCo alloy can enhance the intrinsic catalytic activity of the active site Fe–N4 and prevent the electrolyte corrosion of the metal alloy, ultimately improving the stability of the catalyst by the microenvironment-tailoring strategy. The resultant FePc/NiCo/CNT catalyst exhibits outstanding oxygen reduction reaction (ORR) activity with a half-wave potential of 0.88 V, which is attributed to the abundant Fe–N x active sites. Furthermore, the electron interactions between NiCo/CNT and FePc accelerate electron transfer and enhance the activation of oxygen intermediates, consequently boosting the OER activity with an overpotential of 260 mV at 10 mA cm–2. The Zn-air batteries assembled with FePc/NiCo/CNT show a high power density of 175.1 mW cm–2 and excellent cycling stability for up to 430 h at 20 mA cm–2. The preparation of oxygen electrode catalysts for renewable clean energy devices can be made more convenient with this directly engineered strategy for ORR and OER active centers.