Autonomous Non-Equilibrium Self-Assembly and Molecular Movements Powered by Electrical Energy

The ability to exploit energy autonomously is one of the hallmarks of Life. Mastering such processes in artificial nanosystems can open unforeseen technological opportunities. In the last decades, light- and chemically-driven autonomous systems have been developed in relation to conformational motion and self-assembly, mostly in relation to molecular motors. On the contrary, despite electrical energy is an attractive energy source to power nanosystems, its autonomous exploitation remains essentially unexplored. Herein we demonstrate the autonomous exploitation of electrical energy by a self-assembling system. Threading and dethreading motions of a pseudorotaxane take place autonomously in solution, between the electrodes of a scanning electrochemical microscope. This innovative actuation mode allows operating a molecular machine with an energy efficiency of 9%, unprecedented in autonomous systems. The strategy is general and can be applied to any redox-driven system. Ultimately, our study brings molecular nanoscience one step closer to everyday technology.