• 文献标题:   Preparation and Photophysical and Photoelectrochemical Properties of a Covalently Fixed Porphyrin-Chemically Converted Graphene Composite
  • 文献类型:   Article
  • 作  者:   UMEYAMA T, MIHARA J, TEZUKA N, MATANO Y, STRANIUS K, CHUKHAREV V, TKACHENKO NV, LEMMETYINEN H, NODA K, MATSUSHIGE K, SHISHIDO T, LIU Z, HIROSETAKAI K, SUENAGA K, IMAHORI H
  • 作者关键词:   energy transfer, graphene, photophysic, porphyrinoid, timeresolved spectroscopy
  • 出版物名称:   CHEMISTRYA EUROPEAN JOURNAL
  • ISSN:   0947-6539 EI 1521-3765
  • 通讯作者地址:   Tampere Univ Technol
  • 被引频次:   45
  • DOI:   10.1002/chem.201103843
  • 出版年:   2012

▎ 摘  要

Chemically converted graphene (CCG) covalently linked with porphyrins has been prepared by a Suzuki coupling reaction between iodophenyl-functionalized CCG and porphyrin boronic ester. The covalently linked CCGporphyrin composite was designed to possess a short, rigid phenylene spacer between the porphyrin and the CCG. The composite material formed stable dispersions in DMF and the structure was characterized by spectroscopic, thermal, and microscopic measurements. In steady-state photoluminescence spectra, the emission from the porphyrin linked to the CCG was quenched strongly relative to that of the porphyrin reference. Fluorescence lifetime and femtosecond transient absorption measurements of the porphyrin-linked CCG revealed a short-lived porphyrin singlet excited state (38 ps) without yielding the porphyrin radical cation, thereby substantiating the occurrence of energy transfer from the porphyrin excited state to the CCG and subsequent rapid decay of the CCG excited state to the ground state. Consistently, the photocurrent action spectrum of a photoelectrochemical device with a SnO2 electrode coated with the porphyrin-linked CCG exhibited no photocurrent response from the porphyrin absorption. The results obtained here provide deep insight into the interaction between graphenes and p-conjugated systems in the excited and ground states.