可见光驱动的水氧化,由氧化物集群与单一的Cr中心合在半孔中
1Physical Biosciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|August 17, 2006
概括
研究人员使用可见光开发了一种新的光催化剂,用于利用可见光氧化水. 这种催化剂,具有与氧化物纳米集团连接到 mesoporous silica 上的单个位,有效地驱动水分裂.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 摄影化学的使用.
背景情况:
- 可见光驱动的水氧化对于可再生能源至关重要.
- 开发高效和稳定的光催化剂仍然是一个挑战.
- 半孔二氧化材料为催化剂固定提供可调节的结构.
研究的目的:
- 用一种新型的光催化装置来证明可见光诱导的水氧化.
- 研究孤立位在电子转移中的作用.
- 探索将该单元合到减少站点的潜力.
主要方法:
- 在MCM-41上合成与Cr位点合的氧化纳米集群.
- 使用FT-拉曼,FT-IR和电子显微镜进行表征.
- 在可见光照射下通过质谱仪监测氧气演变.
主要成果:
- 成功组装和表征了IrxOy-CrMCM-41光催化剂.成功组装和表征了IrxOy-CrMCM-41光催化剂.
- 观察到可见光驱动的氧气进化.
- 确定孤立的Cr中心,而不是多色素,对电子提取是活跃的.
结论:
- 在一个与单个金属中心合的多电子转移催化剂中证明了水的氧化.
- 孤立的Cr站点作为氧化集群的高效电子.
- 该系统为集成光催化装置提供了新的可能性.
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