EVOLVE

Nature makes use of outside stimuli to adjust and fashion the properties of biomaterials, providing mechanisms for feedback control, self-repair, and autonomous regulation and, ultimately, evolution. The EVOLVE project aims to progress well beyond the state of the art in molecular electronics by investigating the electronic properties of molecules capable of adapting their morphology in response to the outside environment. This opens up exciting perspectives for the construction of molecular electronic devices whose active layer is composed of chemical objects that adjust and evolve between pre-determined architectures in much the same way that biological materials can change shape and activity in response to their operational environment. This project builds upon recent major discoveries obtained during a previous joint ANR-NSC project (project OLEV, 2010-2013): (i) The straightforward introduction of multiple hydrogen-bonding units onto electro- and photo-active molecules currently used in molecular electronic devices; (ii) the discovery that these lead to the formation of stable supramolecular architectures that retain the electronic and photonic properties of the molecules; and (iii) that it is possible to interconvert between well-defined aggregate structures by exposing the system to an external stimulus. This will allow us to investigate, for the first time, molecular electronic systems in which the active material is capable of adapting to external constraints by changing its morphology. The major goal of this project is to explore how organic systems can adapt to external environments and how this affects their electronic properties in operational devices. The current project brings together four partners, two from Taiwan specialized in organic synthesis of electro-active compounds and surface structural characterization, and two French partners specialized in electro-optical characterization of single chemical objects and molecular electronic device fabrication and characterization. We will prepare and investigate the optical and electronic of molecular devices in which the active layer is composed of molecules that can alter their morphology in response to external stimuli (irradiation, solvent vapors, temperature). In some of these systems, it is possible to reversibly switch between different architectures, opening the way to investigate possible mechanisms of self-repair in molecular electronic devices. We will use template-directed self-assembly to prepare segmented organic nanotubes possessing p-n or p-n-p junctions to investigate their rectifying and photocurrent behavior and how this is affected by changes in their environment. The expected outcome of the project is to develop the next generation of organic materials for molecular electronics that are capable of adjusting their properties (evolving) in response to changes in the operational environment of the device. If successful, this will mark a paradigm shift in the field of organic electronics with potential impact on the design of photovoltaic and light-emitting devices. The project will benefit from a particularly fertile local economic and scientific context thanks to the recently approved ElorPrintTech Equipex and Amadeus Labex projects for printable organic electronics.