Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Organic-inorganic heterostructures with programmable electronic properties

30.03.2017

Researchers from the University of Strasbourg & CNRS (France), in collaboration with the University of Mons (Belgium), the Max Planck Institute for Polymer Research (Germany) and the Technische Universität Dresden (Germany), have devised a novel supramolecular strategy to introduce tunable 1D periodic potentials upon self-assembly of ad hoc organic building blocks on graphene, opening the way to the realization of hybrid organic–inorganic multilayer materials with unique electronic and optical properties. These results have been published in Nature Communications.

Vertical stacks of different two-dimensional (2D) crystals, such as graphene, boron nitride, etc., held together by weak van der Waals forces are commonly referred to as “van der Waals heterostructures”. Such sophisticated multilayer structures can be used as a versatile platform for the investigation of various phenomena at the nanoscale. In particular, mechanical superimposition of the 2D crystals generates 2D periodic potentials which impart to system unconventional physical and chemical properties.


Calculated differential electrical potential induced by a supramolecular lattice of MBB-2 on graphene. The supramolecular lattice is superimposed for clarity. The electrical potential is periodically modulated, with negative values in the region below the molecular heads. Carbon atoms are shown in grey, hydrogen in white, nitrogen in red, fluorine in light blue and chlorine in green. Lohe

Here a team of European researchers applied a supramolecular approach to form self-assembled organic molecular lattices with a controlled geometry and atomic precision on top of graphene, inducing 1D periodic potentials in the resulting organic–inorganic hybrid heterostructures. For that purpose, molecular building blocks were carefully designed and synthesized.

Those are equipped with (i) a long aliphatic tail, directing the self-assembly and the periodicity of the potential, and (ii) a photoreactive diazirine head group, whose dipole moment modulates the surface potential of the underlying graphene sheet. Upon irradiation with ultraviolet (UV) light before deposition on graphene, the diazirine moiety is cleaved and a reactive carbene species is formed. The latter is prone to react with solvent molecules, leading to a mixture of new compounds bearing different functionalities.

Scanning tunneling microscope (STM) imaging was used to characterize the nanoscale arrangement of the supramolecular lattices formed on graphite and graphene surfaces, which determines the periodicity and geometry of the induced potentials. Electrical characterization was then performed on graphene-based field-effect devices to assess the effect of the different self-assembled organic layers on the electrical characteristics of the 2D material.

Computational simulations allowed to unravel the interactions of the molecular assembly with graphene; a theoretical analysis further confirmed that the origin of the doping effects can be fully attributed to the orientation of electrical dipoles in the head groups. Finally, a periodic potential with the same geometry but a different intensity could be generated from a supramolecular lattice prepared after UV irradiation of the molecular building block in a different solvent.

In this way, the researchers managed to demonstrate that organic supramolecular lattices are suitable to create controllable 1D periodic potentials on the surface of graphene. Interestingly, the periodicity, amplitude and sign of the induced potentials can be pre-programmed and adjusted by careful molecular design.

This bottom-up supramolecular approach can be extended and applied to other inorganic 2D materials such as transition metal dichalcogenides, paving the way to more complex multilayer van der Waals heterostructures. These findings are of great importance for the realization of organic–inorganic hybrid materials with controllable structural and electronic properties featuring unprecedented electrical, magnetic, piezoelectric and optical functionalities.

Reference:
“Periodic potentials in hybrid van der Waals heterostructures formed by supramolecular lattices on graphene”
Marco Gobbi, Sara Bonacchi, Jian X. Lian, Yi Liu, Xiao-Ye Wang, Marc-Antoine Stoeckel, Marco A. Squillaci, Gabriele D’Avino, Akimitsu Narita, Klaus Müllen, Xinliang Feng, Yoann Olivier, David Beljonne, Paolo Samorì* & Emanuele Orgiu*
Nature Communications, 2017, 8, 14767
DOI: 10.1038/ncomms14767


Media Inquiries:
Dr. Martin R. Lohe
cfaed Chair for Molecular Functional Materials at TU Dresden
Industry Project Coordinator
Tel.: +49 (0) 351 463-40405 or -43255
E-Mail: martin.lohe@tu-dresden.de

Matthias Hahndorf
cfaed Communications Officer
Tel.: +49 (0)351 463-42847
E-mail: matthias.hahndorf@tu-dresden.de

cfaed
cfaed is a microelectronics research cluster funded by the German Excellence Initiative. It comprises 11 cooperating institutes in Saxony. About 300 scientists from more than 20 countries investigate new technologies for electronic information processing. These technologies are inspired by innovative materials such as silicon nanowires, carbon nanotubes or polymers or based on completely new concepts such as the chemical chip or circuit fabrication methods by self-assembling structures such as DNA-Origami. The orchestration of these new devices into heterogeneous information processing systems with focus on their resilience and energy-efficiency is also part of cfaed’s research program which comprises nine different research paths.

www.cfaed.tu-dresden.de

Kim-Astrid Magister | Technische Universität Dresden

More articles from Power and Electrical Engineering:

nachricht A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes
20.07.2018 | Science China Press

nachricht Future electronic components to be printed like newspapers
20.07.2018 | Purdue University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Enabling technology in cell-based therapies: Scale-up, scale-out or program in-place

23.07.2018 | Health and Medicine

Abrupt cloud clearing events over southeast Atlantic Ocean are new piece in climate puzzle

23.07.2018 | Earth Sciences

The Maturation Pattern of the Hippocampus Drives Human Memory Deve

23.07.2018 | Science Education

VideoLinks
Science & Research
Overview of more VideoLinks >>>