Nitrogen Boosts Defective Vanadium Oxide from Semiconducting to Metallic Merit

Small. 2019 May;15(22):e1900583. doi: 10.1002/smll.201900583. Epub 2019 Apr 8.

Abstract

2D metal oxide nanosheets have attracted substantial attention for various applications owing to their appealing advantages. Yet, the exploration of effective methodology for fabrication of metallic 2D metal oxides with a high concentration of N dopants in a scalable manner remains challenging. Herein, a topochemical strategy is demonstrated on vanadium oxide nanosheets by combining 2D nanostructuring, heteroatom-doping, and defect engineering for modulating their intrinsic electronic structure and greatly enhancing their electrochemical property. O vacancies and N dopants (VON and VN bonds) are in situ formed in vanadium oxide via nitridation and lead to semiconductive-to-metallic phase transformation evidenced by experimental results and theoretical calculation. Overall, the N-VO0.9 nanosheets exhibit a metallic electron transportation behavior and excellent electrochemical performance. These findings shed light on the rational design and electron structure tuning of 2D nanostructures for energy and electronics applications.

Keywords: 2D nanosheet; Li storage; defects; semiconductor-to-metal transition; vanadium oxide.