Journal
CHEMICAL ENGINEERING JOURNAL
Volume 395, Issue -, Pages -Publisher
ELSEVIER SCIENCE SA
DOI: 10.1016/j.cej.2020.125170
Keywords
Water splitting; Oxygen evolution reaction; NiFe2O4; Leaching; Carbon nanosphere
Categories
Funding
- National Natural Science Foundation of China [21603041, 21972124]
- Priority Academic Program Development of Jiangsu Higher Education Institution
- Six Talent Peaks Project of Jiangsu Province [XCL-070-2018]
- Postgraduate Research AMP
- Practice Innovation Program of Jiangsu Province [XKYCX18_045]
- Foundation of Excellent Doctoral Dissertation of Yangzhou University
Ask authors/readers for more resources
A bottleneck is currently met on the very promising NiFe2O4-based catalyst for oxygen evolution reaction (OER) in water splitting. Herein a significantly improved OER catalytic performance was found by selective phosphating of NiFe/NiFe2O4 embedded into porous nitrogen-doped carbon nanosphere (FeNi-FeNiO/CNS), that resulted in structure evolution by transferring the low active sites of FeNi alloy to more active amorphous metal phosphate/NiFe2O4 in the hybrid catalyst (P-FeNiO/CNS). The spectroscopic probing and microscopic observation clearly showed the structure evolution from the hybrid NiFe/NiFe2O4 to metal phosphate/NiFe2O4, and a greatly improved catalytic performance for oxygen evolution was thus obtained even a very low amount of metal was present in the system. Specifically, a quite low overpotential of 220 mV was required on P-FeNiO/CNS loaded on an inert glassy carbon electrode to drive 10 mA cm(-2), about 70 mV less than that of pristine FeNiFeNiO/CNS and 92 mV less than that of the commercial benchmark IrO2 catalyst. The catalytic activity and efficiency also outperformed most of the analogous Fe-Ni based catalysts. The theory analysis demonstrated FeNi alloy had the lowest activity, NiFe2O4 was inferior and metal phosphate/NiFe2O4 had the superior performance for OER. The highly improved catalytic performance on P-FeNiO/CNS could be attributed to the phosphating process resulting in electronic structure modulation, more active sites exposure on the surface and multi-components synergistic effect for the catalytic process. This finding has important implications for OER performance improvement of NiFe2O4 catalysts system and opens a novel way to boost the performance of other NiFe based catalysts for water oxidation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available