A method is provided for making a fabric. The method comprises (a) providing a composition comprising a plurality of nanocrystals disposed in a liquid medium, the nanocrystals comprising a material elected from the group consisting of a Group IV element; (b) applying the composition to a porous substrate, thereby removing at least a portion of the liquid medium from the nanocrystals; and (c) removing the nanocrystals from the porous substrate as a self-supporting mass.