调带间隙和CdS/ZnS异构的传导带边缘 - 一个基于第一原则的预测
Fengai Zhao1, Dingbo Zhang1, Yuxiang Ni1
1School of Physical Science and Technology, Southwest Jiaotong University, Chengdu, Sichuan 610031, China. fazhao@swjtu.edu.cn.
Physical chemistry chemical physics : PCCP
|January 2, 2025
概括
硫化/硫化 (CdS/ZnS) 异构结构显示可调节带间隙,通过水分裂有效生产气. 优化CdS内容可以提高可见光吸收和催化活性.
科学领域:
- 材料科学 材料科学 材料科学
- 光催化作用的光催化
- 计算化学计算化学
背景情况:
- 对于光催化 H2 生产,CdS/ZnS 异构结构是有希望的.
- 调节带间隙对于有效的太阳能/可见光水分离至关重要.
研究的目的:
- 为了预测CdS/ZnS异构结构中的带间隙变化,其组成各不相同.
- 为增强光催化活性确定最佳成分.
主要方法:
- 使用密度函数理论 (DFT) 计算与元-GGA校正.
- 对不同的CdS/ZnS比率分析了带间隙和导电带边缘水平.
主要成果:
- 在异构结构中,CdS和ZnS的带间隙减少了高达14.5%和43.3%.
- CdS内容显著影响带间隙和导电带边缘.
- (CdS) m/(ZnS) n (m>=3,m+n=10) 异构结构表现出可见光吸收的最佳带间隙 (2.06-2.25 eV).
结论:
- 优化的CdS/ZnS异构 (>=30%CdS) 实现可见光吸收的理想带间隙.
- 导电带边缘水平适合通过水分裂生产H2.
- 对CdS/ZnS异构结构的组合调整可以提高光催化剂效率.
相关概念视频
Semiconductors
576
There is variation in the electrical conductivity of materials - metals, semiconductors, and insulators that are showcased with the help of the energy band diagrams.
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...
576
Band Theory
14.9K
When two or more atoms come together to form a molecule, their atomic orbitals combine and molecular orbitals of distinct energies result. In a solid, there are a large number of atoms, and therefore a large number of atomic orbitals that may be combined into molecular orbitals. These groups of molecular orbitals are so closely placed together to form continuous regions of energies, known as the bands.
The energy difference between these bands is known as the band gap.
Conductor, Semiconductor,...
The energy difference between these bands is known as the band gap.
Conductor, Semiconductor,...
14.9K
Energy Bands in Solids
721
Isolated atoms have discrete energy levels that are well described by the Bohr model. And, it quantifies the energy of an electron in a hydrogen atom as En. Higher quantum numbers 'n' yield less negative, closer electron energy levels.
Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
721
Fermi Level Dynamics
220
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
220


