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Regulating Hollow Carbon Cage Supported NiCo Alloy Nanoparticles for Efficient Electrocatalytic Hydrogen Evolution Reaction.
- Source :
-
ACS applied materials & interfaces [ACS Appl Mater Interfaces] 2023 Mar 08; Vol. 15 (9), pp. 12078-12087. Date of Electronic Publication: 2023 Feb 26. - Publication Year :
- 2023
-
Abstract
- The NiCo alloy is one of the most promising alternatives to the noble-metal electrocatalysts for the hydrogen evolution reaction (HER); however, its performance is largely restricted by insufficient active sites and low surface area. Here, we fabricated a hierarchical hollow carbon cage supported NiCo alloy (denoted as HC NiCo/C) and a bulk NiCo alloy (denoted as NiCo) by reduction of a partially ZIF-67 etched ZIF-67@NiCo-LDH (LDH = layered double hydroxide) precursor and a fully ZIF-67 etched NiCo-LDH precursor, respectively. The as-prepared HC NiCo/C, in which the Ni <subscript>29</subscript> Co <subscript>71</subscript> alloy nanocrystals with an average 6 nm size were encapsulated in graphitic carbon layers, provided a vastly increased electrochemically active surface area ( ca . 13 times than the NiCo) and abundant catalytic active sites, which resulted in a higher HER performance with an overpotential of 99 mV than the 198 mV for NiCo at 10 mA cm <superscript>-2</superscript> . Detailed experimental results suggested that only the HC NiCo/C possessed the active alloy surface composed of unsaturated Ni <superscript>0</superscript> and Co <superscript>0</superscript> atoms, and both the metal-support interaction and alloying effect influenced the electronic structure of Co and Ni in HC NiCo/C, whereas the NiCo exhibited pure Ni surface. Theoretical calculations further revealed the Ni <subscript>29</subscript> Co <subscript>71</subscript> alloy surface in HC NiCo/C possessed the appropriate adsorption energy of the intermediate state (adsorbed H*). This work provided new insight into the construction of the stable small-sized bimetallic alloy nanocatalysts by regulating the reduction precursors.
Details
- Language :
- English
- ISSN :
- 1944-8252
- Volume :
- 15
- Issue :
- 9
- Database :
- MEDLINE
- Journal :
- ACS applied materials & interfaces
- Publication Type :
- Academic Journal
- Accession number :
- 36843294
- Full Text :
- https://doi.org/10.1021/acsami.3c00385