6533b7d1fe1ef96bd125cb47

RESEARCH PRODUCT

Photoreactivity of Iron-Doped Titanium Dioxide Powders for Dinitrogen Reduction to Ammonia

subject

description

The production of NH3 from N2 and H2O on Fe/TiO2 has been studied in a continuous photoreactor under UV radiation. An ESR study of the catalysts shows that Fe3+ ions are better electron traps than Ti4+ ions. This trapping can be irreversible if the corresponding holes originate stable species adsorbed on the catalyst surface. The charge separation, thus favoured by the Fe3+ ions, helps the N2 adsorption by its reaction with surface species activated by holes. The best activity is found when no excess Fe is segregated at the surface; overall turnover for N2 reduction as high as 6 e−/Fe atom can be reached before catalyst deactivation.