一个可见光驱动的α-MnO2/UiO-66-NH2 S-Scheme光催化剂,用于改善氧-TCH降解和H2进化
Srabani Dash1, Suraj Prakash Tripathy1, Satyabrata Subudhi2
1Centre for Nanoscience and Nanotechnology, Siksha 'O' Anusnadhan (Deemed to be University), Bhubaneswar 751030, Odisha, India.
Langmuir : the ACS journal of surfaces and colloids
|February 13, 2024
概括
这项研究开发了一种新的α-MnO2纳米改性MOF (MnU) 复合物,用于高效的光催化生产和污染物降解. MnU复合材料显示出高太阳光活性,为能源和环境挑战提供可持续的解决方案.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 环境化学环境化学
- 光催化作用的光催化
背景情况:
- 不同质的光催化为生产和污染物降解提供了一个可持续的途径.
- 开发具有高太阳光吸收率,具有成本效益和环保性的半导体对于解决污染和能源需求至关重要.
- 像UiO-66-NH2这样的金属有机框架 (MOF) 是有前途的,但需要修改以提高光催化活性.
研究的目的:
- 为了合成和描述一种新的α-MnO2纳米改性MOF UiO-66-NH2 (MnU) 复合物.
- 评估MnU复合物的光催化效率对 (H2) 演变和氧四环素化物 (O-TCH) 降解.
- 阐明复合材料中增强光活性背后的机制.
主要方法:
- 简单的溶热合成方法来制备α-MnO2@UiO-66-NH2 (MnU) 混合物.
- 使用场发射扫描电子显微镜 (FESEM),高分辨率传输电子显微镜 (HR-TEM) 和X射线光电子光谱 (XPS) 的表征.
- 通过H2进化和O-TCH光照辐射下的降解实验进行光催化性能评估.
- 使用光发光学 (PL),时间分辨光发光学 (TRPL),电化学阻抗光谱学 (EIS) 和短暂光电流测量,分析电荷载体动态.
主要成果:
- 联混合体表现出纳米嵌入的MOF矩阵结构,证实了成功修改.
- 在MnU复合物中观察到光生成激子的增强分离和更好的电荷转移效率.
- 该MNU-2复合物实现了93.23%的优异O-TCH降解效率和410.6μmolh-1的H2生产率.
结论:
- α-MnO2纳米基基改造显著增强了UiO-66-NH2.2的光催化活性.
- 性能提升归因于更好的电荷分离和传输,可能是通过S-scheme机制.
- 开发的MnU复合物是一个有希望的,高效的光催化剂,用于清洁能源生产和环境修复.
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