Silicon nanowalls have been fabricated on top of p-type silicon (100) wafer using a cost-effective metal assisted chemical etching method. The results obtained from scanning electron and transmission electron microscopies as well as X-ray diffraction studies have shown that the silicon nanowalls are vertically aligned, single crystalline and exhibit the same crystallographic orientation of the base silicon wafer. Spectral reflectance measurements indicate that the silicon nanowalls atop the Si wafer produce very low reflectance signals with a solar-weighted reflectance (R<inf>sw</inf>) value of 1.48% over the wavelength region of interest for crystalline Si solar cells (220–1107 nm), compared to 44% for a polished Si wafer. Wetting contact angle measurements reveal that the silicon wafer surface structured with silicon nanowalls becomes near super-hydrophobic with excellent water repellent properties. © 2020 Elsevier B.V., All rights reserved.