NiCo Alloy Nanoparticles Anchored on Carbon Nanotube-Decorated Carbon Nanorods as a Durable and Efficient Oxygen Electrocatalyst for Zinc-Air Flow Batteries
Wei Peng, Junhong Jin, Shenglin Yang, Zhigang Shen, Hetuan Wang, Jingjing Zhang, Guang Li
Abstract
The exploring of oxygen electrocatalysts with outstanding durability and efficiency toward the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is greatly desired for zinc-air flow batteries (ZAFBs). Herein, NiCo alloy-based nanoparticles anchored on carbon nanotube-decorated carbon nanorods (CNRs) used as a durable and efficient oxygen electrocatalyst for ZAFBs were obtained from the pyrolysis of NiCo metal–organic frameworks synthesized by a facile oil bath method. By tailoring the ratio of Ni2+ and Co2+, the prepared sample, Ni2Co2-CNR, exhibits excellent ORR (E1/2 = 0.80 V) and OER catalytic performances (a low overpotential of 310 mV at 10 mA cm–2). Impressively, the ZAFB assembled with a Ni2Co2-CNR catalyst shows a narrow voltage gap and remarkable operation durability with 1200 cycles at 5 mA cm–2 with every cycle of 20 min.