Programme

P.71 -- Poster, VCTP-49

Date: Friday, 2 August 2024

Time: 08:30 - 10:00

Unrevealing the Roles of Defect Species in Absorption and Photo-degradation of Methylene Blue on the Nitrogen-Doped Anatase TiO2 Surface

Ngoc Linh Nguyen (1)

(1) Faculty of Materials Science and Engineering, Phenikaa University, Hanoi 12116, Vietnam

The utilization of TiO2 nanostructures for photocatalytic applications has garnered significant attention for more than 60 years. Particularly, nitrogen doping of TiO2 surfaces has demonstrated outstanding performance compared to pristine TiO2 in terms of stability and photocatalytic efficiency. In this study, employing first-principles computational methods and combining the standard semi-local approximation with the highly accurate hybrid functional formalism for the exchange-correlation functional, we investigated the energetic and electronic properties of oxygen vacancy and nitrogen-related defects on the (110) surface, known for its high energetic favorability. We elucidate the functional contributions of these defects to enhanced photocatalysis, which include the reduction of the band gap, defect-mediated photoabsorption, and the decrease in electron-hole pair recombination. Particularly noteworthy is the role of the nitrogen substitution oxygen defect in enhancing Methylene Blue absorption, thus increasing catalytic reactivity. Additionally, we conducted a detailed analysis of the stabilization of these defects in relation to their local structures. This analysis offers theoretical insights into the defects' engineering and their potential applications.

Presenter: Ngoc Linh Nguyen