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Zeolitic isolated protonic acid sites-mediated NH3 storage for robust NOx removal
Guobo Li1, Jian Ji1, Meiyuan Liao2
1Engineering Research Center of Watershed Carbon Neutrality of Ministry of Education and School of Resources and Environment, Nanchang University, Nanchang, PR China.
Nature Communications
|July 2, 2026
Summary
This study introduces an oxide-zeolite (OXZEO) hybrid strategy for efficient ammonia selective catalytic reduction (NH3-SCR) catalysts. This design improves NOx emission control across a wide temperature range by separating ammonia storage and redox functions.
Area of Science:
- Materials Science
- Catalysis
- Environmental Science
Background:
- Developing efficient, stable, and wide-temperature ammonia selective catalytic reduction (NH3-SCR) catalysts is crucial for industrial NOx emission control.
- Conventional strategies often rely on Lewis acid sites, facing challenges in stability and temperature window.
Purpose of the Study:
- To present a novel oxide-zeolite (OXZEO) hybrid design strategy for advanced NH3-SCR catalysts.
- To elucidate the unique denitrification (deNOx) mechanism enabled by spatially separated functions in OXZEO systems.
Main Methods:
- Utilized in situ spectroscopy and mass spectrometry for real-time reaction monitoring.
- Employed ab initio molecular dynamics and density functional theory for mechanistic investigations.
- Investigated a CeSnOx/Beta model system and extended findings to diverse zeolite topologies and oxides.
Main Results:
- Identified a novel deNOx mechanism involving zeolitic Brønsted acid sites for regulated NH3 storage.
- Demonstrated that NH3 storage and migration to oxide sites, including NH4+, suppress high-temperature NH3 over-oxidation.
- Achieved >80% NOx conversion and ~100% N2 selectivity over a >300°C temperature window with OXZEO catalysts.
Conclusions:
- The OXZEO strategy effectively separates NH3 storage and redox functions, enhancing catalyst performance.
- Zeolite-mediated NH3 storage provides mechanistic insights into improved deNOx efficiency and stability.
- This approach guides the development of next-generation NH3-SCR catalysts for stringent emission standards.
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