可见光可访问的低能电荷转移激发状态的循环金属化碳III复合体
Spencer T Burton1, Gyunhee Lee1, Curtis E Moore1
1Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43214, United States.
Journal of the American Chemical Society
|April 10, 2025
概括
新的 (III) 复合物作为太阳能和光电还原催化剂具有前景. 复合体3是一种异构的Co (III) 复合体,通过使用绿色光来证明高效的光诱导电荷转移.
科学领域:
- 协调化学
- 光物理学
- 材料科学
背景情况:
- (III) 复合物在太阳能转化和光电还原催化中的潜力得到了探索.
- 了解循环金属化复合物的光物理性质对于开发高效的敏感剂至关重要.
研究的目的:
- 合成和表征新的cis-[Co(ppy) 2 ((L) ]PF6复合物,其中L是一个二胺联体 (bpy,phen,或DAP).
- 调查它们的光物理性质,并评估它们作为太阳能和光电还原催化剂的潜力.
- 探索d6光敏剂的结构设计和激发状态特性之间的关系.
主要方法:
- 三种 (III) 复合物的合成和表征:cis-[Co(ppy) 2 ((bpy) ]PF6 (1),cis-[Co(ppy) 2 ((phen) ]PF6 (2) 和cis-[Co(ppy) 2 ((DAP) ]PF6 (3).
- 包括吸收光谱和短暂吸收光谱在内的光物理性质调查.
- 分析分子轨道相互作用和电子结构的计算研究.
- 包含甲基生物降解的光催化实验.
主要成果:
- 计算显示了强烈的Co (dπ) /ppy (π) 轨道相互作用,导致HOMO局部于Co (dπ) /ppy (π*) 和LUMO在二胺联体上.
- 复合体3呈现出广泛的金属/配体到配体电荷转移 (ML-LCT) 吸收带,最大在507 nm,延伸到600 nm以上.
- 激发1ML-LCT过渡导致3ML-LCT激发状态,复合物1,2和3的寿命分别为3. 0ps,4. 6ps和42ps.
- 在用505nm光照射后,复合物3成功地降低了甲基生物,证明了其光催化活性.
结论:
- 合成的 (III) 复合物具有由二胺联体影响的可调光物理性质.
- 复合体3是第一个报告的异质分子Co(III) 复合体,它结合了循环金属化与二胺联体,具有低的ML-LCT状态,能够在绿色光线下进行光感应的电荷转移.
- 综合体3的结构设计代表了开发用于可持续能源应用的多地金属d6光敏剂的重大进步.
![[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
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