A Pentacene‐based Nanotube Displaying Enriched Electrochemical and Photochemical Activities

A pentacene‐based nanotube was synthesized for the first time. The close proximity of the three non‐conjugated pentacene chromophores allows the nanotube to display stepwise electrochemical/chemical oxidation characteristics. Time‐resolved transient absorption measurements show the generation of an excited triplet state, with a high quantum yield (ca. 180 %) and very long triplet lifetime, through intramolecular singlet fission.

Abstract

Unlike previously well‐studied, acyclic pentacene oligomers, the first synthesis of a cyclic pentacene trimer with a fixed tubular conformation is reported. A short‐step synthesis starting from common pentacenequinone yielded the target molecule with a 1.5 nanometer length and a subnanometer pore. Steady‐state spectroscopic analyses revealed that the close proximity of the non‐conjugated, three pentacene chromophores allows the nanotube to display stepwise electrochemical/chemical oxidation characteristics. Furthermore, time‐resolved transient absorption measurements elucidated the generation of an excited triplet state of the nanotube, with high quantum yield reaching about 180 % through intramolecular singlet fission and a very long triplet lifetime.

from A via a.sfakia on Inoreader http://bit.ly/2Q5OWiX