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Published on: December 6, 2021
Constructing Intermediate Encapsulation on Ru/CeO2 Nanocatalysts to Enhance Ammonia Synthesis
Bingwei Chen1, Xiaojuan Hu1, Jinting Hao1
1Center of Electron Microscopy and State Key Laboratory of Silicon and Advanced Semiconductor Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, China.
Small (Weinheim an Der Bergstrasse, Germany)
|May 24, 2026
Summary
Researchers engineered strong metal-support interactions (SMSI) in ruthenium catalysts by controlling precursor chemistry. This novel approach enhanced ammonia synthesis by creating electron-rich ruthenium sites without blocking active sites.
Area of Science:
- Heterogeneous catalysis
- Materials science
- Surface chemistry
Background:
- Strong metal-support interactions (SMSI) are crucial for tuning catalyst performance by modifying electronic and geometric properties of active sites.
- Designing SMSI that balances active site accessibility and electronic modification remains a significant challenge in catalyst development.
Purpose of the Study:
- To develop a novel strategy for creating intermediate SMSI encapsulation in supported heterogeneous catalysts.
- To investigate the precursor-dependent formation of SMSI and its impact on catalytic activity, specifically for ammonia synthesis.
Main Methods:
- Utilized a Ru-precursor-mediated route to form crystallographically defined CeOx overlayers on Ru/CeO2 catalysts.
- Employed Ru3(CO)12 precursors to create a localized reducing environment, inducing intermediate SMSI overlayers (Ru/CeO2─CO).
- Compared catalysts prepared with Ru(NO)(NO3)3 (Ru/CeO2─NO3) to demonstrate the precursor effect on SMSI formation.
Main Results:
- Successfully formed intermediate, truncated-pyramid-shaped SMSI overlayers (∼2-3 atomic layers) on Ru/CeO2─CO catalysts.
- Ru/CeO2─CO catalysts exhibited significantly higher oxygen vacancy concentrations, promoting electron transfer to Ru nanoparticles.
- The electron-rich Ru species facilitated nitrogen activation, leading to enhanced ammonia synthesis activity without significant active site blockage.
Conclusions:
- A novel strategy for constructing intermediate SMSI encapsulation via precursor control was established.
- The study provides mechanistic insights into how precursor choice influences SMSI formation and catalytic performance at the nanoscale.
- The developed Ru/CeO2─CO catalyst demonstrates a promising approach for efficient ammonia synthesis.
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