Self-Assembled Molecular Rafts at Liquid|Liquid Interfaces for Four-Electron Oxygen Reduction
摘要:
The self-assembly of the oppositely charged water-soluble porphyrins, cobalt tetramethylpyridinium porphyrin (CoTMPyP4+) and cobalt tetrasulphonatophenyl porphyrin (CoTPPS4-), at the interface with an organic solvent to form molecular "rafts", provides an excellent catalyst to perform the interfacial four-electron reduction of oxygen by lipophilic electron donors such as tetrathiafulvalene (TTF). The catalytic activity and selectivity. of the self-assembled catalyst toward the four-electron pathway was found to be as good as that of the Pacman type cofacial cobalt porphyrins. The assembly has been characterized by UV-visible spectroscopy, Surface Second Harmonic Generation, and Scanning Electron Microscopy. Density functional theory calculations confirm the possibility of formation of the catalytic CoTMPyP4+/ CoTPPS4- complex and its capability to bind oxygen.
Electrocatalytic four-electron reduction of oxygen to water by a highly flexible cofacial cobalt bisporphyrin
作者:Christopher J. Chang、Yongqi Deng、Daniel G. Nocera、Chunnian Shi、Fred C. Anson、C. K. Chang
DOI:10.1039/b001620i
日期:——
Dicobalt(II) cofacial bisporphyrins anchored by dibenzofuran (DPD) and xanthene (DPX) are efficient electrocatalysts for the four-electronreduction of oxygen to water despite their ca. 4 A difference in metal–metal distances, suggesting that the considerable longitudinal ‘Pac-Man’ flexibility of the pillared platforms is the origin for the similar catalytic reactivity of these structurally disparate
由二苯并呋喃 (DPD) 和呫吨 (DPX) 锚定的二钴 (II) 共面双卟啉是用于将氧四电子还原成水的有效电催化剂,尽管它们的体积约为 4 金属-金属距离的差异,表明支柱平台具有相当大的纵向“吃豆人”灵活性是这些结构不同的系统具有相似催化反应性的根源。