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Updated: Oct 20, 2025

Monitoring the Effects of Illumination on the Structure of Conjugated Polymer Gels Using Neutron Scattering
Published on: December 21, 2017
Resist or Oxidize: Identifying Molecular Structure-Photostability Relationships for Conjugated Polymers Used in
Ilya V Martynov1, Liana N Inasaridze1, Pavel A Troshin1,2
1Institute of Problems of Chemical Physics, Russian Academy of Sciences, Academician Semenov avenue 1, Chernogolovka, Moscow Region, 142432, Russian Federation.
Abstract:
Although organic solar cells have started to demonstrate competitive power conversion efficiencies of >18 %, their operational lifetimes remain insufficient for wide practical use and the factors influencing the photostability of absorber materials and completed devices are still not completely understood. A systematic study of two series of structurally similar [XTBT]n and [XTTBTBTT]n polymers (16 structures in total) reveals the building blocks that enable the highest material stability towards photooxidation: fluorene, silafluorene, carbazole, diketopyrrolopyrrole, and isoindigo. Furthermore, a direct correlation is evident between the electronic properties of the conjugated polymers and their reactivity towards oxygen. The structures with the lowest highest occupied molecular orbital (HOMO) energies show the highest electrochemical oxidation potentials and appear to be the most resistant towards chemical oxidation. These relationships set important guidelines for the further rational design of new absorber materials for efficient and stable organic photovoltaics.
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