HOPELEC · Harnessing Hopping in Molecular-Scale Electronics: Approaching New Devices 'One Step at a Time'

Harnessing Hopping in Molecular-Scale Electronics: Approaching New Devices 'One Step at a Time'

In a seminal study, Aviram and Ratner proposed that a molecule comprising electron-rich (donor) and electron-poor (acceptor) regions could conduct current better in one direction than the other and so function as a diode or rectifier. Subsequent experimental works have shown that molecules can indeed function as diodes, switches and simple wires, with ongoing efforts to improve functionality. These molecular-electronic systems have the potential to address emerging paradigms in computing at scales smaller than that which can be achieved with conventional materials and with much lower power consumption. However, despite these promising properties, molecular-electronics struggles to realize technologically relevant systems due to the complexity of working on the molecular scale and the complexity of molecule-electrode interactions. This proposal aims to study intramolecular hopping processes that bypass the latter problem in two laboratories; the first focuses on fundamental, single-molecule properties and the second focuses on device-relevant molecular-electronic platforms. The combination of the two-lab approach and the exploitation of intramolecular processes is meant to yield oscillatory molecular-electronic circuits in device-relevant platforms. To exploit and improve our understanding of hopping processes on the nanoscale, the specific objectives of this project are to: (i) identify different classes of redox-active complexes that are stable under the experimental conditions used to probe their charge transport properties; (ii) develop methods to covalently link these individual complexes together into multi-site molecular systems; (iii) synthesize and demonstrate the first single-molecule current oscillator by exploiting intramolecular charge hopping in a junction (Fig 1a); (iv) prepare linear multi-site systems comprising a redox-potential gradient as hopping-based current rectifiers (Fig 1b); (v) compare charge transport through the same molecules at the single-molecule scale using STM-BJ and in large-area measurements using EGaIn. My previous experience studying electron transfer in redox systems (ligand and multi-metallic complex syntheses, spectroelectrochemistry) positions me particularly well to tackle this highly interdisciplinary area. The Fellowship will significantly enhance my international profile through publications in high impact journals and multinational networking activities. The new synthetic methods, scanning probe/EGaIn techniques and fundamental concepts explored here will broaden my capabilities in nanoscience, inspiring further novel ideas which will be exploited subsequently in pursuit of my independent academic career.

Data: CORDIS, © European Union