# Titania-Based Oxide Catalysts for Removing Nitrogen Oxides

## TL;DR

This paper explores titania-based catalysts with cerium, copper, or iron for efficiently removing nitrogen oxides at moderate temperatures.

## Contribution

The study introduces new titania-based catalysts with cerium and iron that show high activity without forming harmful N2O.

## Key findings

- Catalysts with cerium and iron showed high activity for nitrogen oxide reduction between 200-400 °C.
- The materials had a mesoporous structure with a specific surface area of 74-160 m2/g.
- High catalytic activity was attributed to Fe3+ or Ce3+ ions on the material's surface.

## Abstract

Titania catalysts containing cerium, copper, or iron were obtained using the sol–gel method and tested in the selective reduction of nitrogen oxide. Samples with cerium and iron showed high activity at temperatures ranging from 200 to 400 °C, without the formation of N2O. The materials crystallized in anatase structure, and only a small amount of ceria was detected by XRD. Their crystallites were nanometric in size. The solids were mesoporous, with a specific surface area between 74 and 160 m2/g, determined based on nitrogen sorption at low temperature. The optimum Ce/Ti and Fe/Ti atomic ratio was 0.1 to 0.9, and such catalysts were composed of small anatase crystallites, although the presence of ceria also resulted in high catalytic activity. This activity was due to the presence of Fe3+ or Ce3+ ions on the surface of the material.