(492e) ‘Spring-Like' and Photomechanical Junctions Between Nanoparticles: An Avenue to Power Molecular-Machines by Compression Energy

Integrating molecular elasticity and dynamics into nanoelectronics has potential to enable the development of next-generation nanoelectromechanical systems like energy storage devices, molecular timers and actuators, which could be integrated to build self-sustaining molecular machines. The major challenges to building such a system are (a) providing mechanism for application of confined forces acting on or generated by the molecular-junction, (b) fabrication of strong chemically-bonded molecular-junctions, which will not fail upon mechanical deformation and (c) having a nano-scale mechanically mobile system to achieve unrestrained mechanics. Such molecular mechanics cannot be achieved in a device construct where molecular junctions are incorporated between ?rigid' electrodes. We are studying the operation of a ?molecular-spring? nanodevice, where controllable and confined forces are applied on molecular junctions and which can store compression and stretching energy. The system is built with covalently/electrostatically crosslinked polyelectrolyte (carbon-chains or photo-active) (cPE) molecules sandwiched between gold nanoparticles (GNP), where cPE molecular-junctions are reversibly compressed and stretched by applying electrically and centrifugally induced forces respectively, while GNPs play a dual role (a) of movable connectors to apply forces and (b) of nanoelectrodes to measure molecular deformation via change in electron tunneling conductivity. These ?molecular-spring' junctions can thus be compressed and stretched, and can subsequently apply forces on the nanoparticles to bring them back to their native state. We are studying the dynamics of these junctions. Also, we are investigating a light-actuated molecular junction (azo-group) between metal-nanoparticles. Here, the inherent mechanical actuation of azo-group is used to controllably manipulate the attached nanoparticles. We are investigating the dynamics of this system for reversible light-induced-actuation of nanoparticles. The ability to store compression energy in a molecular-device-architecture and to manipulate them by actuating junctions has the potential to power future molecular devices by stored molecular-energy and controlling the properties of nanocomponent based devices.