Boosting the bifunctional oxygen electrocatalytic performance of atomically dispersed Fe site via atomic Ni neighboring

By Mang Ma, Anuj Kumar, Danni Wang, Yiyan Wang, Yin Jia, Ying Zhang, Guoxin Zhang, Zifeng Yan, Xiaoming Sun. 2020

169 citations recorded by the source corpus.

Abstract Atomically dispersed metal-nitrogen-carbon complexes on carbon supports have drawn tremendous attention in the electrocatalysis fields. Herein, we managed the synthesis of atomically dispersed binary NixFe100-x-NC (x = 0–100) materials with tunable Ni/Fe ratios and investigated their underneath synergy effects for the enhancement of oxygen reduction (ORR) and oxygen evolution reactions (OER). EXAFS revealed the abundant presence of Ni(N3)-Fe(N3)-Cn moieties in Ni66Fe34-NC sample. XPS fine scans indicated deep synergy of dual-site Ni/Fe that favored more charge localized over Ni/Fe sites. Electrochemical measurments showed that the Ni66Fe34-NC delivered a very high ORR half-wave potential (E1/2) of 0.85 V and a low OER overpotential of 467 mV at ∼10 mA cm−2 (Ej=10). The Fe site with Ni neighboring, as suggested by DFT simulations and in-situ Raman, was the responsible site for both ORR and OER. Furthermore, the Ni66Fe34-NC-assembled Zn-air battery afforded large specific power density and extraordinary cycling stability.

Subfields: Electrical and Electronic Engineering, Renewable Energy, Sustainability and the Environment

View Paper: https://www.semanticscholar.org/paper/3c0a4cfa14265621f069dcca327962fc909e7c91