1. Strong metal-support interaction facilitated the formation of ternary alloy and interfacial oxygen vacancies for enhanced overall water splitting.
- Author
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Bai, Xue, Liu, Jiangyong, Wang, Jing, Chang, Kuang, and Yan, Xiaodong
- Subjects
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TERNARY alloys , *CERIUM oxides , *HYDROGEN evolution reactions , *OXYGEN evolution reactions , *SURFACE area , *ELECTROCATALYSIS - Abstract
The NiCoFe-based alloys are potential high-performing bifunctional electrocatalysts towards overall alkaline water splitting, though it is still challenging to achieve this goal. Herein, the NiCoFe/CeO 2-x heterostructure with abundant interfacial oxygen vacancies is constructed through in - situ hydrogenation. The strong metal-support interaction favors the formation of the medium-entropy NiCoFe ternary alloy and the interfacial oxygen vacancies, while the introduction of the cobalt highly increases the electrochemically active surface area (ECSA). The ECSA of the NiCoFe/CeO 2-x is more than 3 times those of the NiCoFe, NiFe/CeO 2-x , NiCo/CeO 2-x and CoFe/CeO 2-x. Therefore, the NiCoFe/CeO 2-x shows high catalytic performance towards both hydrogen evolution reaction and oxygen evolution reaction with a small overpotential of 42 and 238 mV at 10 mA cm−2 in 1 M KOH, respectively. More importantly, the NiCoFe/CeO 2-x heterostructure with optimal elemental composition demonstrates excellent catalytic performance towards overall water splitting, exhibiting a small cell voltage of 1.52 V at 10 mA cm−2 without i R compensation. In addition, it shows good working stability in the overall water splitting at 100 mA cm−2 during a period of >10 h. • The strong metal-support interaction favors the NiCoFe ternary alloy formation. • The NiCoFe/CeO 2-x possesses abundant interfacial oxygen vacancies. • The introduction of Co greatly enhances the electrochemically active surface area. • The NiCoFe/CeO 2-x is highly active towards both hydrogen and oxygen evolution. • The high activity is due to the synergistic effect between NiCoFe and CeO 2-x. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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