Publication

Long‐Lived Photocharges in Supramoelcular Polymers of Low‐Bandgap Chromophores

Abstract

Photoinduced charge separation in supramolecular aggregates of π‐conjugated molecules is a fundamental photophysical process, and a key criterion for the development of advanced organic electronics materials. Here, we report on the self‐assembly of novel low‐bandgap chromophores into helical one‐dimensional aggregates due to intermolecular hydrogen‐bonding. The chromophores confined in these supramolecular polymers show strong excitonic coupling interactions and give rise to charge‐separated states with unusually long lifetimes of several hours and charge densities of up to 5 mol% after illumination with white light. Two‐contact devices exhibit increased photoconductivity and can even show Ohmic behavior. Our findings demonstrate that the confinement of organic semiconductors into one‐dimensional aggregates results in a considerable stabilization of charge carriers for a variety of π‐conjugated systems, which may have implications for the design of future organic electronic materials.

About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
Related concepts (32)
Organic electronics
Organic electronics is a field of materials science concerning the design, synthesis, characterization, and application of organic molecules or polymers that show desirable electronic properties such as conductivity. Unlike conventional inorganic conductors and semiconductors, organic electronic materials are constructed from organic (carbon-based) molecules or polymers using synthetic strategies developed in the context of organic chemistry and polymer chemistry.
Organic semiconductor
Organic semiconductors are solids whose building blocks are pi-bonded molecules or polymers made up by carbon and hydrogen atoms and – at times – heteroatoms such as nitrogen, sulfur and oxygen. They exist in the form of molecular crystals or amorphous thin films. In general, they are electrical insulators, but become semiconducting when charges are either injected from appropriate electrodes, upon doping or by photoexcitation. In molecular crystals the energetic separation between the top of the valence band and the bottom conduction band, i.
Semiconductor
A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way. Its conducting properties may be altered in useful ways by introducing impurities ("doping") into the crystal structure. When two differently doped regions exist in the same crystal, a semiconductor junction is created.
Show more
Related publications (42)

Drift-Diffusion Simulations of Charge Transport and Trap Dynamics in Organic Semiconductor Materials

Camilla Arietta Vael-Garn

Polymeric semiconductors have gained significant attention in the field of organic electronics due to their unique properties and potential applications. Through their ability to transport charge carriers and to absorb or emit light, they have attracted mu ...
EPFL2023

Scrutinizing thermally stimulated current transients originating from trapped charges in organic semiconductors: A drift-diffusion study

Beat Ruhstaller

Thermally stimulated current (TSC) is a widely used technique to assess trap states and extract their density, energy, and capture rate using analytical expressions. In many cases, the latter are derived from physical models pertaining to inorganic semicon ...
AIP Publishing2022

Semiaromatic polyamides with enhanced charge carrier mobility

John Christopher Plummer, Holger Frauenrath, Nicolas Candau

The control of local order in polymer semiconductors using non-covalent interactions may be used to engineer materials with interesting combinations of mechanical and optoelectronic properties. To investigate the possibility of preparing n-type polymer sem ...
ROYAL SOC CHEMISTRY2021
Show more

Graph Chatbot

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.