Nanostructures and photovoltaic structures are disclosed. A nanostructure according to one embodiment includes an array of nanocables extending from a substrate, the nanocables in the array being characterized as having a spacing and surface texture defined by inner surfaces of voids of a template; an electrically insulating layer extending along the substrate; and at least one layer overlaying the nanocables. A nanostructure according to another embodiment includes a substrate; a portion of a template extending along the substrate, the template being electrically insulative; an array of nanocables extending from the template, portions of the nanocables protruding from the template being characterized as having a spacing, shape, and surface texture defined by previously-present inner surface of voids of the template; and at least one layer overlaying the nanocables.