研究目的
Investigating the electronic structures and optical properties of metallic and nonmetallic elements-doped ZnO based on the principle of photocatalysis by first-principle density functional theory.
研究成果
The band structures, DOS and optical properties of pure ZnO and single metallic or nonmetallic element-doped ZnO are evaluated by first-principle density functional theory calculation, aiming to investigate the effect of elements doping on the photocatalytic properties of ZnO. The calculated results indicate that the p-type doping can introduce valance states into band gap of ZnO, which acts as the 'springboard' for shortening the band gap and enhancing the light absorbing abilities of the photocatalysts. In addition, the p-type doping elements increase the Fermi-level DOS, which are beneficial to improve the excitation of photoinduced electrons and thus enhance photocatalytic performance of ZnO.
研究不足
The calculated band gap of pure ZnO by CASTEP package is 0.80 eV, which is much lower than 3.2 eV obtained by the experiment, exhibiting the general shortcoming of the GGA function in the first-principle calculation.
1：Experimental Design and Method Selection:
First-principles calculations based on density functional theory (DFT) with CASTEP package of materials studio
2：0 (MS 0). The exchange correlation potential between the atomic nucleus and valence electrons was described by the generalized gradient approximation (GGA) with the function of Perdew Burke Ernzerh (PBE). Sample Selection and Data Sources:
The hexagonal wurtzite ZnO possesses stable structure and good photocatalytic performance. Doping elements including metallic (Fe, Cu, Cd) and nonmetallic (B, N, S) were selected.
3：List of Experimental Equipment and Materials:
Plane wave basis was set cut-off energy of 340 eV. A 4 × 4 × 2 gird of Monkhort-Pack points were used in this study for geometry optimization and related calculation.
4：Experimental Procedures and Operational Workflow:
Geometric optimization was achieved using convergence thresholds of 2×10?5 eV per atom for total energy,
5：05 eV ?-1 for maximum force, 1 GPa for pressure, and 002 ? for maximum displacement. After geometry optimization, the band structures, density of states and optical properties of different models were calculated. Data Analysis Methods:
The band structures, total and projected density of states (TDOS and PDOS) and optical properties were analyzed.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
