Light-Harvesting and Ultrafast Energy Migration in Porphyrin-Based Metal-Organic Frameworks

被引：520

作者：

Son, Ho-Jin ^{[1
]}

Jin, Shengye ^{[2
]}

Patwardhan, Sameer ^{[1
]}

Wezenberg, Sander J. ^{[1
]}

Jeong, Nak Cheon ^{[1
,3
]}

So, Monica ^{[1
]}

Wilmer, Christopher E.

Sarjeant, Amy A. ^{[1
]}

Schatz, George C. ^{[1
]}

Snurr, Randall Q.

Farha, Omar K. ^{[1
]}

Wiederrecht, Gary P. ^{[2
]}

Hupp, Joseph T. ^{[1
]}

机构：

[1] Northwestern Univ, Dept Chem, Evanston, IL 60208 USA

[2] Argonne Natl Lab, Ctr Nanoscale Mat, Argonne, IL 60439 USA

[3] DGIST, Dept Emerging Mat Sci, Taegu, South Korea

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2013年 / 135卷 / 02期

关键词：

ELECTRONIC SPECTROSCOPY; OPTICAL-PROPERTIES; CHARGE-TRANSPORT; DYNAMICS; COMPLEX; PHOTOSYNTHESIS; CHLOROPHYLL; ASSEMBLIES; POLYMERS; DESIGN;

D O I：

10.1021/ja310596a

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Given that energy (exciton) migration in natural photosynthesis primarily occurs in highly ordered porphyrin-like pigments (chlorophylls), equally highly ordered porphyrin-based metal-organic frameworks (MOFs) might be expected to exhibit similar behavior, thereby facilitating antenna-like light-harvesting and positioning such materials for use in solar energy conversion schemes. Herein, we report the first example of directional, long-distance energy migration within a MOF. Two MOFs, namely F-MOF and DA-MOF that are composed of two Zn(II) porphyrin struts [5,15-dipyridyl-10,20-bis(pentafluorophenyl)porphinato]zinc(II) and [5,15-bis[4-(pyridyl)ethynyl]-10,20-diphenylporphinato]zinc(II), respectively, were investigated. From fluorescence quenching experiments and theoretical calculations, we find that the photogenerated exciton migrates over a net distance of up to similar to 45 porphyrin struts within its lifetime in DA-MOF (but only similar to 3 in F-MOF), with a high anisotropy along a specific direction. The remarkably efficient exciton migration in DA-MOF is attributed to enhanced p-conjugation through the addition of two acetylene moieties in the porphyrin molecule, which leads to greater Q-band absorption intensity and much faster exciton-hopping (energy transfer between adjacent porphyrin struts). The long distance and directional energy migration in DA-MOF suggests promising applications of this compound or related compounds in solar energy conversion schemes as an efficient light-harvesting and energy-transport component.

引用

页码：862 / 869

页数：8

共 42 条

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