Selective no loss transportation of water droplets based on the superhydrophobic surfaces with controllable high water adhesion

Abstract

Superhydrophobic ZnO surfaces with controllable high water adhesion have been fabricated by combining both construction of ZnO structures on zinc substrates and the subsequent modification of 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PDTMS). Different surface morphologies were obtained on the zinc substrates by changing the concentration ratio of (NH4)2S2O8/NaOH and temperature during the hydrothermal process. After being modified with PDTMS, the as-prepared surfaces show analogous superhydrophobicity but controllable high water adhesion, which ranges from 3 to 5 μL, 8 and 10 μL. Based on the different high water adhesion on the superhydrophobic surfaces, the selective no loss water transportation with different volumes has been achieved. We believed that the results reported here would be potentially used in microfluidic systems to manipulate the liquid droplets.