氧硫化物Sm{2) Ti{2) S{2) O{5) 作为稳定的光催化剂,在可见光照射下氧化和减少水 (lambda <或 = 650 nm)
Akio Ishikawa1, Tsuyoshi Takata, Junko N Kondo
1Chemical Resources Laboratory, Tokyo Institute of Technology, Nagatsuta 4259, Midori-ku, Yokohama 226-8503, Japan.
Journal of the American Chemical Society
|November 7, 2002
概括
氧硫化 (Sm(2) Ti(2) S(2) O(5)) 显示为一个稳定的,可见光驱动的光催化剂. 它有效地从水中产生和氧气,显示出强大的降解和氧化能力.
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
- 无机化学 无机化学 有机化学
背景情况:
- 可见光驱动的光催化对于可持续能源和环境应用至关重要.
- 开发利用可见光光谱的稳定高效光催化剂仍然是一个重大挑战.
- 基于的氧硫化物正在成为一种具有潜在光催化活性的材料.
研究的目的:
- 在可见光照射下,研究一种新的基于Ti的氧硫化物Sm(2) Ti(2) S(2) O(5) 的光催化特性.
- 阐明电子带结构并确定Sm(2)Ti(2)S(2)O(5) 的带隙能量.
- 评估Sm(2)Ti(2)S(2)O(5) 在水分裂反应中的稳定性和氧化还原能力.
主要方法:
- Sm(2)Ti(2)S(2)O(5) 的合成和表征.
- 使用牺牲剂进行可见光光催化实验,用于H2和O2的进化.
- 使用密度函数理论 (DFT) 计算电子带结构.
- 电化学测量以确定带边的位置.
主要成果:
- Sm{2) Ti{2) S{2) O{5) 显示出高效的可见光驱动的光催化活性,在不降解的情况下产生H{2) 和O{2).
- 该材料具有大约2 eV的带隙,归因于形成价值带的S3p轨道.
- 电化学测量证实了适合的波段边缘潜力在pH 8下减少水和氧化.
结论:
- Sm{2) Ti{2) S{2) O{5) 是一种稳定有效的可见光光催化剂,具有显著的还原和氧化潜力.
- 电子结构,特别是S3p轨道的贡献,是其可见光吸收和光催化性能的关键.
- 这种氧硫化物对太阳能燃料生产和环境修复的应用非常有前途.
相关概念视频
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