Solvent-mediated assembly of atom-precise gold-silver nanoclusters to semiconducting one-dimensional materials

Bottom-up design of functional device components based on nanometer-sized building blocks relies on accurate control of their self-assembly behavior. Atom-precise metal nanoclusters are well-characterizable building blocks for designing tunable nanomaterials, but it has been challenging to achieve directed assembly to macroscopic functional cluster-based materials with highly anisotropic properties. Here, we discover a solvent-mediated assembly of 34-atom intermetallic gold-silver clusters protected by 20 1-ethynyladamantanes into 1D polymers with Ag-Au-Ag bonds between neighboring clusters as shown directly by the atomic structure from single-crystal X-ray diffraction analysis. Density functional theory calculations predict that the single crystals of cluster polymers have a band gap of about 1.3eV. Field-effect transistors fabricated with single crystals of cluster polymers feature highly anisotropic p-type semiconductor properties with approximate to 1800-fold conductivity in the direction of the polymer as compared to cross directions, hole mobility of approximate to 0.02 cm(2) V-1 s(-1), and an ON/OFF ratio up to approximate to 4000. This performance holds promise for further design of functional cluster-based materials with highly anisotropic semiconducting properties. Bottom-up design of functional device components based on nanometer-sized building blocks relies on accurate control of their self-assembly behavior. Here, the authors demonstrate a solvent-mediated polymerization of atom-precise gold-silver nanoclusters into macroscopic single crystals with highly anisotropic p-type semiconducting characteristics.