Recrystallized NaCl from thin film to nano-micro sized sacrificial crystal for metal nanostructures

We developed a breakthrough method for preparing metallic nanostructures using self-assembled NaCl nano sized sacrificial crystal and applied it to i) transparent flexible electrodes and ii) as catalysts for Si nanorod fabrication. Au nanostructures fabricated using the NaCl sacrificial crystal on a polyethylene terephthalate substrate showed low resistance (40 Ω/sq), relatively high transmittance (73%), and excellent mechanical stability. Wet chemical etching of Si with Ag nanostructures formed on a Si (100) substrate using the NaCl sacrificial crystal produced uniform vertical Si microrods with a thickness of 1–2 μm and length of about 3–4 μm. These Si microrods showed high light absorption (over 90%) in the wavelength range 350–800 nm, and various applications in optoelectronic devices are expected in future.