A Roadmap for Mechanically Interlocked Molecular Junctions at Nanoscale

Abstract

The beauty and utility of mechanically interlocked architectures have received considerable notice from scientists in the past several decades. Plentiful scientific and technological achievements have been made and developed because of conjoining mechanically interlocked molecules (MIMs) and molecular electronic devices at nanoscale. The interaction mechanisms and translational dynamics of various MIMs, e.g., rotaxanes, catenanes, and daisy chains, have been investigated systemically through different experimental methods. On account of the recent advances of single-molecule techniques, the electrical and mechanical performance of mechanically interlocked molecular junctions (MIMJs) or nanodevices have been explored in a timely manner. In this Review, we survey the field of MIMs from a perspective of unique structural properties including topological features, translational dynamics, bistable switching properties, insulation effects, and dynamic stability present in MIMs. We then give a fundamental description of electron transport mechanisms in MIMJs for three different nanodevice geometries: (i) monolayer switching tunnel junctions (MSTJs), (ii) single-molecule junctions (SMJs) based on MIMs, and (iii) real-time transistor-like platforms.

Multistate Structural Switching of [3]Catenanes with Cyclic Porphyrin Dimers by Complexation with Amine Ligands

“…To verify this concept, a [3]catenane 4 comprising two kinds of cyclic metalloporphyrin dimers with rigid π-conjugated backbones was designed. Taking advantage of the high tailorability of the molecular structure of amine ligands, we achieved the ligand-controlled multistate switching of [3] 4,6,8,10,12,16,32). This is the first example of a catenane that can switch between multiple structural states using organic ligands as external stimuli.…”

“…Mechanically interlocked molecules are advantageous for a variety of applications owing to their flexible mechanical bonds [1–8] . In particular, interlocked macrocyclic structures, such as catenanes, are promising components for molecular motors, [9–11] optical materials, [12–14] and polymeric materials [15–18] because of the switchable structural states of catenanes, including the relative positions or dynamics of their cyclic components [19–21] .…”

Characterization and Application of Supramolecular Junctions

“…In this section, we highlight the most remarkable breakthroughs achieved in recent years regarding intermolecular interactions, such as π‐π stacking interactions, hydrogen bonds, host‐guest interactions and σ‐σ interactions, ranging from essential characterization to modulations and dynamic investigations. It should be noted that the studies of mechanically interlocked molecules and parallel circuits are out of our scope, which is summarized in other reviews [1, 15a] …”

Molecular Nanotechnology for Tomorrow’s World: A Forum Dedicated to Professor Sir Fraser Stoddart on the Occasion of His 80th Birthday

“…15 Yang and Chen provided a comprehensive roadmap to highlight the mechanically interlocked molecular junctions or nanodevices with fundamental descriptions of the electron-transport mechanisms. 16 Liu et al summarized tetraphenylethylene-based nanocages and macrocycles for their potential applications in detection, sensing, imaging, and catalysis. 17 Han and coauthors discussed the research progress of cyclodextrin-based aerogels for adsorption of environmental pollutants, thermal insulation, and electrochemical sensors.…”

“…Pasini and co-workers reviewed the research progress on single-chain polymer nanoparticles having various morphologies and functions . Yang and Chen provided a comprehensive roadmap to highlight the mechanically interlocked molecular junctions or nanodevices with fundamental descriptions of the electron-transport mechanisms . Liu et al summarized tetraphenylethylene-based nanocages and macrocycles for their potential applications in detection, sensing, imaging, and catalysis .…”