Ozone Decomposition below Room Temperature Using Mn-based Mullite YMn₂O₅

Area of Science:

• Materials Science
• Catalysis
• Environmental Chemistry

Background:

• Ozone (O3) decomposition is crucial for air purification and environmental remediation.
• Existing catalysts often require high temperatures or energy input for efficient ozone decomposition.
• Developing low-temperature catalysts is essential for energy-efficient environmental applications.

Purpose of the Study:

• To develop a novel catalyst for efficient ozone decomposition at super-low temperatures.
• To investigate the catalytic mechanism and durability of the proposed catalyst.
• To establish a new benchmark for low-temperature ozone decomposition catalysts.

Main Methods:

• Synthesis and characterization of the ternary oxide catalyst YMn2O5.
• Ozone decomposition activity testing at temperatures down to -40 °C.
• Durability assessment through extended reaction testing.
• Surface analysis using O2-temperature-programmed desorption (O2-TPD).
• In situ Raman spectroscopy and density functional theory (DFT) calculations to elucidate the reaction mechanism.

Main Results:

• YMn2O5 demonstrated efficient ozone decomposition starting at -40 °C, reaching 100% conversion at -5 °C.
• The catalyst exhibited excellent durability, maintaining its structure and performance after 100 hours of reaction.
• Active sites were identified as Mn3+ sites with singly coordinated oxygen.
• DFT calculations revealed a low activation barrier (0.29 eV) following the Eley-Rideal mechanism.

Conclusions:

• YMn2O5 is a highly effective catalyst for low-temperature ozone decomposition without energy consumption.
• The catalyst's performance is attributed to moderate Mn-O bonding strength and specific active sites.
• This finding presents a significant advancement in developing energy-efficient ozone degradation technologies.