Single-molecule diodes with high rectification ratios through environmental control

Abstract

Molecular electronics aims to miniaturize electronic devices by using subnanometre-scale active components. A single-molecule diode, a circuit element that directs current flow, was first proposed more than 40 years ago and consisted of an asymmetric molecule comprising a donor-bridge-acceptor architecture to mimic a semiconductor p-n junction. Several single-molecule diodes have since been realized in junctions featuring asymmetric molecular backbones, molecule-electrode linkers or electrode materials. Despite these advances, molecular diodes have had limited potential for applications due to their low conductance, low rectification ratios, extreme sensitivity to the junction structure and high operating voltages. Here, we demonstrate a powerful approach to induce current rectification in symmetric single-molecule junctions using two electrodes of the same metal, but breaking symmetry by exposing considerably different electrode areas to an ionic solution. This allows us to control the junction's electrostatic environment in an asymmetric fashion by simply changing the bias polarity. With this method, we reliably and reproducibly achieve rectification ratios in excess of 200 at voltages as low as 370 mV using a symmetric oligomer of thiophene-1,1-dioxide. By taking advantage of the changes in the junction environment induced by the presence of an ionic solution, this method provides a general route for tuning nonlinear nanoscale device phenomena, which could potentially be applied in systems beyond single-molecule junctions.

Principles of a Single-Molecule Rectifier in Electrolytic Environment

“…21 Not aware of refs 19 and 20, Capozzi et al 21 seemed to reproduce the main qualitative conclusion of those works: the possibility to achieve rectification in electrolytic environment. In our present paper, we explore all aspects of the rectification effect that have not been studied in the original refs 19 and 20, thus providing a comprehensive extension of that theory.…”

Poly(3-hexylthiophene) Nanoparticles Containing Thiophene-S,S-dioxide: Tuning of Dimensions, Optical and Redox Properties, and Charge Separation under Illumination

“…[1][2][3][4][5][6] In addition, the recent development of simple methods for their preparation has enabled the synthesis of unexplored families of sulfur-oxygenated oligoand polythiophenes with potential applications spanning from organic electronics to chemical biology. [7][8][9][10][11][12][13][14][15][16][17][18][19] The incorporation of strong electron acceptor TDO moieties deeply affects the HOMO-LUMO energy levels of the material causing a substantial reduction of the energy gap.…”

Высокая Подвижность Носителей Заряда В Молекулярных Каналах Полианилина В Нанозазорах Между Углеродными Нанотрубками

“…Молекулярная наноэлектроника предполагает созда-ние функциональных элементов на основе манипулиро-вания и управления свойствами одиночных молекул [1]. Одним из базовых элементов молекулярной наноэлек-троники является одномолекулярный транзистор, в ко-тором проводимость осуществляется через одиночную органическую молекулу (или малую группу таких мо-лекул) [2][3][4].…”