Atomically Dispersed MoOx on Rhodium Metallene Boosts Electrocatalyzed Alkaline Hydrogen Evolution
Jiandong Wu1, Jinchang Fan1, Xiao Zhao1
1State Key Laboratory of Automotive Simulation and Control, School of Materials Science and Engineering, Key Laboratory of Automobile Materials of MOE, Jilin University, Changchun, 130012, China.
Angewandte Chemie (International Ed. in English)
|June 28, 2022
Summary
Developing a novel MoOx-Rh catalyst significantly enhances the alkaline hydrogen evolution reaction (HER). This interface engineering boosts HER activity, offering a promising alternative to platinum-based catalysts.
Area of Science:
- Materials Science
- Electrochemistry
- Catalysis
Background:
- Efficient hydrogen evolution reaction (HER) in alkaline media is crucial for renewable energy technologies.
- Slow water dissociation kinetics currently limits the performance of many HER electrocatalysts.
- Developing cost-effective and highly active catalysts is essential for widespread adoption.
Purpose of the Study:
- To synthesize and characterize a novel catalyst for accelerated alkaline HER.
- To investigate the role of oxide-metal interfaces in enhancing catalytic activity.
- To provide insights into the mechanism of water dissociation and hydrogen evolution.
Main Methods:
- One-pot solvothermal synthesis of atomically dispersed MoOx species on Rh metallene.
- Electrochemical characterization of the MoOx-Rh catalyst for alkaline HER.
- First-principles calculations to elucidate the catalytic mechanism at the oxide-metal interface.
Main Results:
- The MoOx-Rh catalyst exhibits ultrahigh activity for alkaline HER, with a mass activity of 2.32 A mgRh-1 at 50 mV overpotential.
- Achieved activity is 11.8 times higher than commercial Pt/C and surpasses existing Rh-based catalysts.
- Interface between MoOx and Rh identified as the active center for water dissociation and H2 evolution.
Conclusions:
- Atomic interface engineering of MoOx-Rh is a highly effective strategy for boosting alkaline HER.
- The synergistic effect between MoOx and Rh facilitates water splitting and hydrogen adsorption.
- This approach offers a promising pathway for developing next-generation electrocatalysts for hydrogen production.
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