CORDIS - EU research results

"MOLECULAR-SCALE ELECTRONICS: Concepts, Contacts and Stability ""MOLESCO"""

Final Report Summary - MOLESCO (MOLECULAR-SCALE ELECTRONICS: Concepts, Contacts and Stability "MOLESCO")

MOLESCO ITN Project number 606728
Publishable Summary for the period 01/01/2014 to 31/12/2017

Project Objectives:
There are four closely integrated S&T objectives (O1-O4) which will be delivered through four Work Packages (WP1-4). To ensure the delivery of these objectives, the consortium will implement a highly-integrated approach with embedded training in the experimental and theoretical aspects of molecular electronics. Our objectives are:
• O1. Design and synthesis of new functional molecules with anchor groups tailored to the chosen electrode.
• O2. Fabrication of electrode–molecule–electrode junctions using Pt, Pd or graphene electrodes.
• O3. Mechanical and electrical stability of single-molecule junctions, probed using atomic force microscopy (AFM), break-junction and STM measurements, combined with first principles theory.
• O4. Control of charge transport and switching in molecular junctions via a gate electrode, electric field in a two-terminal geometry or electrochemical gating.

Description of the work performed.
The existing collaborations between many of the MOLESCO partners, as a result of their participation in the previous FP7 ITN “FUNMOLS” (project number 212942) enabled the MOLESCO consortium to make rapid progress from the start of the project. Excellent progress has been maintained throughout the four years in all aspects of the project with the planned milestones and deliverables being achieved for all of the objectives listed above. The project had considerable momentum in the implementation of the training and transfer of knowledge, research outputs, and development of impact and visibility at the European level. The MOLESCO funding was a catalyst for many new collaborations which developed between the partners, associate partners and groups outside the Network. A large number of highly collaborative and intersectoral projects were initiated and are continuing post-MOLESCO.

The main results achieved.
• New molecules have been synthesized with redox-active core units, and molecules designed to probe different possible pathways of conduction between to electrodes in electrode-molecule-electrode assemblies. Molecules have been synthesized which exploit quantum interference to modulate their conduction behaviour: STM break junction data have been supported by theoretical calculations. Graphene has been covalently modified with fullerene derivatives. Few-layer graphene devices have been fabricated by electroburning and molecules inserted into the gaps. STM images have been obtained of molecular structures covalently embedded into graphene nanoribbons. Simultaneous thermopower and conductance measurements have been obtained on fullerenes and fluorene-based molecular wires. A modified UHV-STM setup has been developed in the unique Noise Free labs at IBM Zurich. The goal here is to combine thermal and electrical measurement in order to simultaneously extract the thermal and electrical conductance. Control of charge transport and switching has been achieved in single-molecule junctions by embedding redox-active or spin cross-over moieties within the molecules.
• To date 111 publications from the consortium have been published in peer-reviewed journals, reporting work undertaken within the framework of MOLESCO. Many of these publications involve two or more Network partners. These include articles in high impact international journals such as Journal of the American Chemical Society, NanoLetters, Nanoscale, Nature Communications, Nature Materials, and Chemical Society Reviews. The publication list from our activities is available on the MOLESCO website:

Final results and their potential impact and use.
It is widely acknowledged that within the next 10-15 years the fundamental size limitations of silicon-based technology will need to be overcome by a bottom-up approach. A transition to sub-10 nm electronics will require new materials and new devices, for which molecular-electronic materials have high promise. Attractive features of such materials include intrinsic functionalities integrated into their molecular structure and the availability of identical building blocks defined at the atomic scale. MOLESCO has taken molecular electronics beyond the current state-of-the-art and has delivered: (i) a comprehensive understanding of electron transport and switching in molecular junctions with metal or graphene electrodes; and (ii) new paradigms for single-molecule electronics, which overcome recognised roadblocks and deliver unprecedented molecular-scale switching functionality. By bringing together world-leading experts in molecular- and nano-electronics, MOLESCO has ensured that a cohort of researchers have gained the most-up-to-date knowledge and skills for a technology in which conventional silicon technology is supplemented and eventually replaced by sub-10 nm nanoelectronic building blocks

This ITN has linked the activities of world-leading pan-European groups and trained researchers in an area of nanotechnology with immense potential for new discoveries and future wealth creation. The strong combination of academic and private sector partners has provided the critical mass needed for wide ranging impact. The ITN has:
• Enhanced the EU’s basic understanding of future molecular-scale electronics.
• Increased the efficiency of pre-competitive research.
• Trained the next generation of researchers in a wide breadth of interdisciplinary and intersectoral scientific and transferable skills. “Well-developed human resources in R&D are the cornerstone of advancement in scientific knowledge and technological progress” (The European Charter for Researchers).
• Reduced fragmentation and ensure long-term cohesion of molecular electronic research in Europe.
• Increased the awareness of the general public to advances in molecular electronics, nanoscience and technology.