Monocrystalline epitaxially aligned nanostructures and related methods

A nanostructure comprising:

• monocrystalline substrate comprising a first monocrystalline material having a first crystal structure;
• and
• a plurality of monocrystalline pillars located epitaxially aligned with, extending contiguously from, and directly contacting the monocrystalline substrate, each of the plurality of monocrystalline pillars comprising a second monocrystalline material having a height above the Matthews-Blakeslee limit for thin film heteroepitaxial growth for the second monocrystalline material and bulk second crystal structure with a lattice mismatch of +/−0.1 to about 10.0 percent with respect to the first crystal structure, absent any lattice mismatch induced crystal structure defects interposed between the monocrystalline substrate and the plurality of epitaxially aligned contiguous monocrystalline pillars,
• wherein each of the plurality of monocrystalline pillars is formed by a single-step energetic treatment comprising a fluence that is sufficient to melt and rapidly cool the first monocrystalline material of, at least in part, an upper surface of the monocrystalline substrate exposed through a plurality of pores disposed within a template layer located on an upper surface of the monocrystalline substrate, wherein the height is from 1 micron to 10 microns, and the template layer located on the upper surface of the monocrystalline substrate is formed by a self-assembling polymer to generate the plurality of pores.