Iron-modulated nickel cobalt phosphide embedded in carbon to boost power density of hybrid sodium–air battery

Yao Kang, Shuo Wang, Siqi Zhu, Haixing Gao, Kwan San Hui, Cheng Zong Yuan, Hong Yin, Feng Bin, Xi Lin Wu, Wenjie Mai, Ling Zhu, Maocong Hu, Feng Liang, Fuming Chen, Kwun Nam Hui

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)

Abstract

Nickel cobalt phosphide (NiCoP) is emerging as a potential electrocatalyst towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). However, its ORR/OER activities are sluggish. Here, we investigated the roles of iron dopants in the Fe-doped NiCoP (Fe–NiCoP) in order to boost its ORR/OER kinetics. The density functional theory (DFT) calculations reveal that the Fe dopant effectively modulates the electron conductivity of NiCoP and reduces binding energies of the reaction intermediates towards rate-determining steps of ORR and OER. A binder-free 3D microflowers morphology of the Fe–NiCoP embedded in the amorphous carbon layer (Fe–NiCoP@C) catalyst on the nickel foam was prepared as the air cathode for the hybrid sodium-air battery (HSAB). The HSAB displays a discharge voltage of 2.74 V at 0.01 mA cm−2 with excellent round trip efficiency of 93.26 % at the 500th cycle and state-of-the-art power density of 621 mW g−1.

Original languageEnglish
Article number119786
JournalApplied Catalysis B: Environmental
Volume285
Early online date10 Dec 2020
DOIs
Publication statusPublished - 15 May 2021

Keywords

  • DFT calculation
  • Electronic structure reformation
  • Hybrid sodium-air battery
  • Iron doping
  • Nickel cobalt phosphide

Cite this