Alkynyl and halogen co-protected (AuAg)44 nanoclusters: a comparative study on their optical absorbance, structure,
Yun Tang1, Fang Sun2, Xiaoshuang Ma1
1Guangzhou Key Laboratory for Surface Chemistry of Energy Materials, New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, Guangdong, 510006, P. R. China. zhht@scut.edu.cn.
We synthesized two gold-silver (AuAg) alloy nanoclusters for the hydrogen evolution reaction (HER). NC 1 demonstrated superior HER activity and stability compared to NC 2 due to a more favorable hydrogen binding energy.
Area of Science:
- Nanomaterials Science
- Catalysis
- Electrochemistry
Background:
- Gold-silver (AuAg) alloy nanoclusters are promising catalysts.
- Understanding structure-activity relationships is crucial for optimizing performance.
- Electrochemical hydrogen evolution reaction (HER) is a key process for clean energy.
Purpose of the Study:
- To synthesize and characterize AuAg alloy nanoclusters.
- To investigate their structural differences and HER performance.
- To elucidate the factors governing their catalytic activity.
Main Methods:
- Synthesis of alkynyl and halogen coprotected AuAg nanoclusters (NC 1 and NC 2).
- Single crystal X-ray structural analysis.
- Electrochemical testing for HER performance and stability.
- Density functional theory (DFT) calculations.
Main Results:
- Two AuAg nanoclusters, NC 1 (Au24Ag20) and NC 2 (Au22Ag22), were synthesized.
- Both exhibited similar core@shell@shell structures but differed in the outermost shell composition.
- NC 1 showed significantly higher HER activity and stability than NC 2.
- DFT calculations revealed lower hydrogen binding energy for NC 1, indicating a more feasible HER pathway.
Conclusions:
- Subtle differences in the outermost shell of AuAg nanoclusters drastically impact HER performance.
- NC 1 is a superior HER catalyst due to optimized hydrogen binding.
- These findings provide insights for designing efficient noble metal alloy nanocluster catalysts.
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