Constructions of hierarchical nitrogen doped carbon nanotubes anchored on CoFe2O4 nanoflakes for efficient hydrogen evolution, oxygen evolution and oxygen reduction reaction
JiaJun Lai, ChuagWang Zeng, Siyuan Peng, QiHong Zhou, Jinming Zeng, Chao Liu, Xiaopeng Qi
Abstract
The three primary reactions in metal-air batteries and electrochemical hydrolysis are the hydrogen evolution reaction (HER), the oxygen evolution reaction (OER), and the oxygen reduction reaction (ORR). Therefore, it is crucial to develop efficient low-cost trifunctional catalysts. In this study, we design a self-supported electrocatalyst with hierarchical nanostructure , in which the bamboo-like nitrogen doped carbon nanotubes (NCNTs) encapsulated CoFe nanoparticles (CoFe NPs) in-situ anchored on nanoflower like CoFe 2 O 4 via chemical vapor deposition . Strikingly, the resulting catalysts CoFe@NC/CoFe 2 O 4 /IF demonstrate exciting trifunctional catalytic performance, overpotential of 66 mV and 185 mV for HER and OER at current densities of 10 mA cm −2 , and a half-wave potential of 0.852 V for ORR, respectively. In addition, the maximum power density of the Zinc-air batteries (ZABs) assembled with CoFe@NC/CoFe 2 O 4 /IF as the cathode electrode is 134.5 mW cm −2 ; and the overall water splitting requires only a voltage of 1.50 V at a decomposition current density at 10 mA cm −2 . This method provides a new strategy for trifunctional electrocatalysts and offers a promising approach for self-driven water electrolysis devices.