Phase-dependent photo-assisted electrocatalytic nitrate-to-ammonia conversion on TiO2: Insights into amorphous and rutile activity

Phase-dependent photo-assisted electrocatalytic reduction of nitrate to ammonia was studied using titanium dioxide (TiO2) as the catalyst. By comparing amorphous and rutile TiO2, the work demonstrates how structural order and electronic properties influence charge transfer and the formation of key reaction intermediates during nitrate conversion.

The synergistic effect of illumination and applied potential enables nitrate reduction under mild conditions, with amorphous TiO2 displaying superior activity due to a higher density of active sites and enhanced charge separation.

Continuous, real-time detection of gaseous products via quadrupole mass spectrometry allowed direct correlation between catalyst structure and reaction performance.

These results underscore the role of defect engineering and phase control in the design of advanced catalysts for sustainable ammonia synthesis, offering a greener, more energy-efficient alternative to conventional processes.

Figure 1. Comparison of amorphous and rutile TiO2 phases in photo-electrocatalytic nitrate reduction.

Project Summary by: Jacinto Sá, Uppsala Universitet, Dag Hammarskjölds Väg 7, 752 37, Uppsala, Sweden.

Paper Reference: Silveira, V. R., Fernandes, D. F., Bericat-Vadell, R., Edvinsson, T., Kubart, T. and Sá, J. (2024) Phase-dependent photo-assisted electrocatalytic conversion of nitrate to ammonia using TiO2: Insights into amorphous and rutile activity. Applied Catalysis O Open. Elsevier BV, November, pp. 207017–207017. DOI: 10.1016/j.apcato.2024.207017.

Hiden Product: HPR-20 R&D.