Charge-Transfer Intermediates in the Electrochemical Doping Mechanism of Conjugated Polymers

2020 ◽  
Author(s):  
Ilaria Bargigia ◽  
Lisa R. Savagian ◽  
Anna M. Österholm ◽  
John R. Reynolds ◽  
Carlos Silva
Keyword(s):  
Charge Transfer ◽  
Conjugated Polymers ◽  
Electrochemical Doping ◽  
Doping Mechanism

scholarly journals Charge-Transfer Intermediates in the Electrochemical Doping Mechanism of Conjugated Polymers

2020 ◽  
Author(s):  
Ilaria Bargigia ◽  
Lisa R. Savagian ◽  
Anna M. Österholm ◽  
John R. Reynolds ◽  
Carlos Silva
Keyword(s):  
Charge Transfer ◽  
Conjugated Polymers ◽  
Transient Absorption ◽  
Electronic Conductivity ◽  
Environmental Parameters ◽  
Local Environment ◽  
Precursor State ◽  
Electrochemical Doping ◽  
Heterogeneous Polymer

In this work, we address the nature of electrochemically induced charged states in conjugated polymers, their evolution as a function of electrochemical potential, and their coupling to their local environment by means of transient absorption and Raman spectroscopies synergistically performed in situ throughout the electrochemical doping process. In particular, we investigate the fundamental mechanism of electrochemical doping in an oligoether-functionalized 3,4-propylenedioxythiophene (ProDOT) copolymer. The changes embedded in both linear and transient absorption features allow us to identify a precursor electronic state with charge-transfer (CT) character that precedes polaron formation and bulk electronic conductivity. This state is shown to contribute to the ultrafast quenching of both neutral molecular excitations and polarons. Raman spectra relate the electronic transition of this precursor state predominantly to the C<sub>β</sub> -C<sub>β</sub> stretching mode of the thiophene heterocycle. We characterize the coupling of the CT-like state with primary excitons and electrochemically induced charge separated states, providing insight into the energetic landscape of a heterogeneous polymer-electrolyte system and demonstrate how such coupling depends on environmental parameters, such as polymer structure, electrolyte composition, and environmental polarity.<br>

scholarly journals Charge-Transfer Intermediates in the Electrochemical Doping Mechanism of Conjugated Polymers

2020 ◽  
Author(s):  
Ilaria Bargigia ◽  
Lisa R. Savagian ◽  
Anna M. Österholm ◽  
John R. Reynolds ◽  
Carlos Silva
Keyword(s):  
Charge Transfer ◽  
Conjugated Polymers ◽  
Transient Absorption ◽  
Electronic Conductivity ◽  
Environmental Parameters ◽  
Local Environment ◽  
Precursor State ◽  
Electrochemical Doping ◽  
Heterogeneous Polymer

In this work, we address the nature of electrochemically induced charged states in conjugated polymers, their evolution as a function of electrochemical potential, and their coupling to their local environment by means of transient absorption and Raman spectroscopies synergistically performed in situ throughout the electrochemical doping process. In particular, we investigate the fundamental mechanism of electrochemical doping in an oligoether-functionalized 3,4-propylenedioxythiophene (ProDOT) copolymer. The changes embedded in both linear and transient absorption features allow us to identify a precursor electronic state with charge-transfer (CT) character that precedes polaron formation and bulk electronic conductivity. This state is shown to contribute to the ultrafast quenching of both neutral molecular excitations and polarons. Raman spectra relate the electronic transition of this precursor state predominantly to the C<sub>β</sub> -C<sub>β</sub> stretching mode of the thiophene heterocycle. We characterize the coupling of the CT-like state with primary excitons and electrochemically induced charge separated states, providing insight into the energetic landscape of a heterogeneous polymer-electrolyte system and demonstrate how such coupling depends on environmental parameters, such as polymer structure, electrolyte composition, and environmental polarity.<br>

Enhanced Electrochemical Doping Kinetics in Conjugated Polymers by Blending with Hydrophilic Block Copolymers

2019 ◽  
Author(s):  
Micah Barker ◽  
Tommaso Nicolini ◽  
Georges Hadziioannou ◽  
Natalie Stingelin
Keyword(s):  
Block Copolymers ◽  
Conjugated Polymers ◽  
Electrochemical Doping

scholarly journals Conjugated Polymer Donor-Molecular Acceptor Nanohybrids for Photocatalytic Hydrogen Evolution

2019 ◽  
Author(s):  
Haofan Yang ◽  
Xiaobo Li ◽  
Reiner Sebastian Sprick ◽  
Andrew I. Cooper
Keyword(s):  
Photocatalytic Activity ◽  
Charge Transfer ◽  
Conjugated Polymers ◽  
Hydrogen Evolution ◽  
Conjugated Polymer ◽  
Apparent Quantum Yield ◽  
High Hydrogen ◽  
Photocatalytic Hydrogen Evolution ◽  
Efficient Charge ◽  
Donor Acceptor

A library of 237 organic binary/ternary nanohybrids consisting of conjugated polymers donors and both fullerene and non-fullerene molecular acceptors was prepared and screened for sacrificial photocatalytic hydrogen evolution. These donor-acceptor nanohybrids (DANHs) showed significantly enhanced hydrogen evolution rates compared with the parent donor or acceptor compounds. DANHs of <a></a><a>a polycarbazole</a>-based donor combined with a methanofullerene acceptor (PCDTBT/PC<sub>60</sub>BM) showed a high hydrogen evolution rate of 105.2 mmol g<sup>-1</sup> h<sup>-1</sup> under visible light (λ > 420 nm). This DANH photocatalyst produced 5.9 times more hydrogen than a sulfone-containing polymer (P10) under the same conditions, which is one of the most efficient organic photocatalysts reported so far. An apparent quantum yield of hydrogen evolution of 3.0 % at 595 nm was measured for this DANH. The photocatalytic activity of the DANHs, which in optimized cases reached 179.0 mmol g<sup>-1</sup> h<sup>-1</sup>, is attributed to efficient charge transfer at the polymer donor/molecular acceptor interface. We also show that ternary donor<sub>A</sub>-donor<sub>B</sub>-acceptor nanohybrids can give higher activities than binary donor-acceptor hybrids in some cases.

Universal ultrafast signatures of photoexcitations in conjugated polymers: excitons and charge-transfer polarons

1999 ◽  
Author(s):  
Duncan W. McBranch ◽  
Brett Kraabel ◽  
Su Xu ◽  
Hsing-Lin Wang ◽  
Victor I. Klimov
Keyword(s):  
Charge Transfer ◽  
Conjugated Polymers

scholarly journals Design principles for the energy level tuning in donor/acceptor conjugated polymers

2019 ◽  
Vol 21 (2) ◽  
pp. 789-799 ◽  
Author(s):  
Daniel Hashemi ◽  
Xiao Ma ◽  
Ramin Ansari ◽  
Jinsang Kim ◽  
John Kieffer
Keyword(s):  
Charge Transfer ◽  
Energy Level ◽  
Conjugated Polymers ◽  
Transfer Process ◽  
Design Principles ◽  
Charge Transfer Process ◽  
Frontier Orbitals ◽  
Donor Acceptor ◽  
Homo And Lumo

Illustration of the charge transfer associated with the development of HOMO and LUMO levels in conjugated polymers and that the electron donating and withdrawing powers depend on the collective of atoms that carry the frontier orbitals involved in the charge transfer process.

Interaction of Oxygen with Conjugated Polymers:  Charge Transfer Complex Formation with Poly(3-alkylthiophenes)

1997 ◽  
Vol 119 (19) ◽  
pp. 4518-4524 ◽  
Author(s):  
Mohamed S. A. Abdou ◽  
Francesco P. Orfino ◽  
Yongkeun Son ◽  
Steven Holdcroft
Keyword(s):  
Charge Transfer ◽  
Complex Formation ◽  
Conjugated Polymers ◽  
Charge Transfer Complex
Sign in / Sign up

Export Citation Format

Share Document