为了控制水氧化催化:与轴性伊米达/DMSO连接体的鲁复合物的可调节活性
Lei Wang1, Lele Duan, Beverly Stewart
1Department of Chemistry, Royal Institute of Technology, Stockholm, Sweden.
Journal of the American Chemical Society
|October 16, 2012
概括
复合物与伊米达和DMSO轴联体显示了不同的水氧化催化剂 (WOC) 活性. 一个轴向的DMSO组显著提高了周转频率,一个复合体达到~180秒~-1).
科学领域:
- 协调化学 协调化学
- 催化剂是一种催化剂.
- 可再生能源可再生能源是可再生能源.
背景情况:
- 水氧化催化剂 (WOCs) 对于人工光合作用和燃料生产至关重要.
- 复合体是有希望的WOC候选者,但它们的活性高度依赖于连接体设计.
- 了解结构-活动关系是开发高效WOC的关键.
研究的目的:
- 为了合成和描述新型的复合物与伊米达和二甲基硫氧化物 (DMSO) 作为轴联体.
- 研究这些复合物在水氧化中的催化活性.
- 阐明它们作为WOCs的表现所支配的结构-活动关系.
主要方法:
- 合成了六种新型的 ((II) 复合物,其中以 2,2'-二二-6,6'-二碳酸盐 (bda) 作为赤道配体.
- 使用动力学,电化学,高分辨率质谱学 (HR-MS) 进行详细的表征.
- 使用密度函数理论 (DFT) 计算的机械研究.
主要成果:
- 四个C(s) 对称的和两个C(2v) 对称的复合物已成功合成和表征.
- 催化活性有显著的变化,含有轴向DMSO组的复合物表现出增强的周转频率.
- 一个复合物与一个轴向的5--N-甲基-伊米达和一个轴向的DMSO实现了高初始周转频率~180s(-1).
- DFT 建模支持了轴联体在 O-O 键形成中的机理意义.
结论:
- 复合体中的轴联体的性质对水氧化催化活性产生了深刻的影响.
- 结合一个轴向的DMSO连接体,大大增加了WOCs的周转频率.
- 这些发现为设计高效的以为基础的氧化水催化剂提供了宝贵的见解.
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