Adsorption of NO<sub>2</sub> and H<sub>2</sub>S on ZnGa<sub>2</sub>O<sub>4</sub>(111) Thin Films: A First-Principles Density Functional Theory Study
oleh: Jen-Chuan Tung, Yi-Hung Chiang, Ding-Yuan Wang, Po-Liang Liu
| Format: | Article |
|---|---|
| Diterbitkan: | MDPI AG 2020-12-01 |
Deskripsi
We performed first-principles total-energy density functional calculations to study the reactions of NO<sub>2</sub> and H<sub>2</sub>S molecules on Ga–Zn–O-terminated ZnGa<sub>2</sub>O<sub>4</sub>(111) surfaces. The adsorption reaction and work functions of eight NO<sub>2</sub> and H<sub>2</sub>S adsorption models were examined. The bonding of the nitrogen atom from a single NO<sub>2</sub> molecule to the Ga atom of the Ga–Zn–O-terminated ZnGa<sub>2</sub>O<sub>4</sub>(111) surfaces exhibited a maximum work function change of +0.97 eV. The bond joining the sulfur atom from a single H<sub>2</sub>S molecule and the Ga atom of Ga–Zn–O-terminated ZnGa<sub>2</sub>O<sub>4</sub>(111) surfaces exhibited a maximum work function change of −1.66 eV. Both results concur with previously reported experimental observations for ZnGa<sub>2</sub>O<sub>4</sub>-based gas sensors.