Electrically Conductive Copper Core-shell Nanowires through Benzenethiol-directed Assembly.

Ultrathin nanowires with < 3 nm diameter have long been sought for novel properties that emerge from dimensional constraint as well as for continued size reduction and performance improvement of nanoelectromc devices. Here, we report on a facile and large-scale synthesis of a new class of electrically conductive ultrathin core-shell nanowires using benzenethiols. Core-shell nanowires are atomically precise and have inorganic five-atom copper-sulfur cross-sectional cores encapsulated by organic shells encompassing aromatic substituents with ring planes oriented parallel. The exact nanowire atomic structures were revealed via a two-pronged approach combining computational methods coupled with experimental synthesis and advanced characterizations. Core-shell nanowires were determined to be mdirect bandgap materials with a predicted room-temperature resistivity of similar to 120 Omega-m. Nanowire morphology was found to be tunable by changing the mterwire interactions imparted by the functional group on the benzenethiol molecular precursors, and the nanowire core diameter was determined by the stenc bulkiness of the ligand. These discoveries help define our understanding of the fundamental constituents of atomically well-defined and electrically conductive core-shell nanowires, representing significant advances toward nanowire building blocks for smaller, faster, and more powerful nanoelectronics.