Altering Hydrogenation Pathways in Photocatalytic Nitrogen Fixation by Tuning Local Electronic Structure of Oxygen Vacancy with Dopant

To avoid the energy-consuming step of direct N equivalent to N bond cleavage, photocatalytic N-2 fixation undergoing the associative pathways has been developed for mild-condition operation. However, it is a fundamental yet challenging task to gain comprehensive understanding on how the associative pathways (i.e., alternating vs. distal) are influenced and altered by the fine structure of catalysts, which eventually holds the key to significantly promote the practical implementation. Herein, we introduce Fe dopants into TiO2 nanofibers to stabilize oxygen vacancies and simultaneously tune their local electronic structure. The combination of in situ characterizations with first-principles simulations reveals that the modulation of local electronic structure by Fe dopants turns the hydrogenation of N-2 from associative alternating pathway to associative distal pathway. This work provides fresh hints for rationally controlling the reaction pathways toward efficient photocatalytic nitrogen fixation.

Automated summary

This study introduces Fe dopants into TiO2 nanofibers to stabilize oxygen vacancies and tune their local electronic structure, shifting the hydrogenation of N-2 from an associative alternating pathway to an associative distal pathway. This approach provides new insights for efficiently controlling reaction pathways towards photocatalytic nitrogen fixation.