ZnO nano structure arrays on silicon substrate using chemical treatment have been developed. The morphology of nanostructures formulated thereafter was characterized using Field Emission Scanning Electron Microscope (FESEM), X-Ray Diffraction (XRD), Energy-Dispersive X ray Spectroscopy (EDAX). These structures are envisioned for Hydrogen sensing. High reconditionability with moderate sensitivity has been achieved with the developed nanostructures. © 2013 AIP Publishing LLC.