Moving charge and matter with self-assembled molecular Brownian motors

Rather than fighting thermal noise, Brownian motors (or ratchets) make use of the ubiquitous thermal energy to perform useful work. Moreover, they can do so very efficiently, and in situations where the interaction forces are of the order of the thermal energy. Despite the above, the actual use of ratchets in operational applications is currently very limited. In this project, two devices are pursued. A molecular current source, in which an AC electric drive is rectified into a DC charge movement, and a size-selective molecular sieve, in which the size-dependent movement of (bio)molecules or nanoparticles is used for fractionation. Both devices are based on the ratchet principle. Ultimately, the ratchet potential will be formed by molecular self-assembly on a suitably chosen substrate, rather than by top-down lithographic techniques. The project aims at delivering working devices that serve as a proof of principle for each of the concepts.