论文标题
工程2D卟啉桨轮金属有机框架的电子和光学特性
Engineering the electronic and optical properties of 2D porphyrin paddlewheel metal-organic frameworks
论文作者
论文摘要
金属有机框架（MOF）由于其高表面积和电子结构的可调性而具有有希望的光催化材料。 We discuss here how to engineer the band structures and optical properties of a family of two-dimensional (2D) porphyrin-based MOFs, consisting of M tetrakis(4 carboxyphenyl)porphyrin structures (M TCPP, where M = Zn2+ or Co2+) and metal (Co2+, Ni2+, Cu2+ or Zn2+) paddlewheel clusters, with the aim of optimising their太阳能燃料合成反应中的光催化行为（水分和/或二氧化碳减少）。基于密度功能理论（DFT）和具有杂种功能的时间依赖性DFT模拟，我们研究了三种类型的组成/结构修饰：a）改变桨轮或卟啉中心的金属中心，以修改带对对准； b）部分将卟啉单位降低到氯蛋白，从而导致可见光的吸收更强； c）用Ethyne或Butadiyne Bridges代替卟啉和桨轮之间的苯桥接，以将连接器修改为金属电荷转移行为。我们的工作提供了有关如何改善基于卟啉和桨轮的MOF的光催化行为的新见解。
Metal organic frameworks (MOFs) are promising photocatalytic materials due to their high surface area and tuneability of their electronic structure. We discuss here how to engineer the band structures and optical properties of a family of two-dimensional (2D) porphyrin-based MOFs, consisting of M tetrakis(4 carboxyphenyl)porphyrin structures (M TCPP, where M = Zn2+ or Co2+) and metal (Co2+, Ni2+, Cu2+ or Zn2+) paddlewheel clusters, with the aim of optimising their photocatalytic behaviour in solar fuel synthesis reactions (water splitting and/or CO2 reduction). Based on density functional theory (DFT) and time-dependent DFT simulations with a hybrid functional, we studied three types of composition/structural modifications: a) varying the metal centre at the paddlewheel or at the porphyrin centre to modify the band alignment; b) partially reducing the porphyrin unit to chlorin, which leads to stronger absorption of visible light; and c) substituting the benzene bridging between the porphyrin and paddlewheel, by ethyne or butadiyne bridges, with the aim of modifying the linker to metal charge transfer behaviour. Our work offers new insights on how to improve the photocatalytic behaviour of porphyrin- and paddlewheel-based MOFs.
