In-situ construction of Schottky junctions with synergistic interaction of oxygen vacancies in Mo@MoO3 nanosheets for efficient N2 photoreduction

Defect engineering is a promising technique that can activate nitrogen by injecting electrons into the anti-bonding molecular orbital of nitrogen through anion vacancies. Moreover, compared to a single component, Schottky junctions can effectively overcome rapid electron recombination, thereby significantly enhancing photoelectron utilization efficiency. In this work, we prepared Mo modified MoO3 nanosheets with abundant oxygen vacancies by a solvothermal method and investigated the effect of synergistic interactions between Schottky junctions and oxygen vacancies on the photocatalytic performance of N-2 reduction reaction (NRR). The photocatalytic nitrogen fixation performance of Mo@MoO3 nanosheets (MoO3-6) reached 50.78 mu mol center dot g(-1)center dot h(-1) without any scavenger, which was about 3 times that of commercial MoO3. The Schottky barrier creates a built-in electric field generating charge transfer channels during the photocatalytic reaction, while the oxygen vacancies trap electrons to activate N-2, and together with Mo, broaden the light absorption range of the catalyst, facilitating more efficient transfer of excited electrons to the active site. The synergetic advantages of Schottky junctions and oxygen vacancies are exploited in advancing the photocatalytic effect, providing new opportunities and challenges for the development of metal oxide-based materials.

Automated summary

Defect engineering technique of injecting electrons into nitrogen using anion vacancies is promising for activating nitrogen. Schottky junctions can enhance photoelectron utilization efficiency by overcoming electron recombination. In this study, Mo modified MoO3 nanosheets with oxygen vacancies were prepared and the synergetic effects of Schottky junctions and oxygen vacancies on N-2 reduction reaction photocatalytic performance were investigated. The Mo@MoO3 nanosheets showed a nitrogen fixation performance three times higher than commercial MoO3. The advantages of Schottky junctions and oxygen vacancies in improving photocatalytic effects were explored, providing new opportunities for metal oxide-based materials.