In this work, a series of naphthalimide fused thienopyrazine derivatives was designed in order to efficiently modulate both the energy and topology of the frontier molecular orbitals involved in the charge transport mechanism.
22 February 2024 in Advanced Energy and Sustainability Research
In the field of organic solar cells, organic semiconductors with Y6‐based chemical structure and their corresponding quinoxaline‐based assemblies are settled down as promising materials in the field of OSCs. However, the chemical structure of Y6 derivatives does not allow an expansion in the electron‐withdrawing central core, in contrast to their quinoxaline‐based analogues. For this reason, herein, two different quinoxaline‐based A–D–A′–D–A derivatives with 2D π‐extended cores endowed with electroactive rylenimide moieties, named as Y6‐1Napht and Y6‐1Pery, are designed and synthesized. These enlarged fused‐ring electron acceptors (FREAs) allow to study the influence of the length of the ryleneimide moiety on its structural, optical, electrochemical, and thermal properties as well as the tailoring of the frontier molecular orbitals. These results are also supported by quantum chemical calculations and photoluminescence measurements that provide additional information about their thermal stability and the microstructure of the films. Finally, as a proof of concept and to study the influence of these chemical modifications on the central core, solar cells based on these π‐conjugated nonfullerene acceptors are fabricated.
In this work, a series of nitrogen-doped polycyclic aromatic mono and dicarboximides was designed, and their synthesis is reported by an innovative synthetic procedure that avoids metal-based cross-coupling reactions. A combined theoretical, electrochemical, optical spectroscopy and material characterization study allows the investigation of the interplay of different effects such as (i) the type of solubilizing chain, (ii) the all-acceptor vs. donor–acceptor nature of the novel systems, and (iii) the molecular ordering, on the ability to stabilize multiple charges and on the OTFT device response characteristics. The amphoteric redox behavior of some of the novel systems allow to obtain ambipolar mobilities while the electron mobility values of the three all-acceptor systems can be rationalized in terms of supramolecular aggregation and enhanced film-forming ability.
A conjugated two-dimensional poly(azomethine) network based on ambipolar terthiophene–naphthalimide assemblies has been synthesized and its electrochemical and UV-vis absorption properties have been investigated.