Rapid Reversible Superhydrophobicity to Superhydrophilicity Conversion of HF-Tuned ZnO Flower-Like Micro-Sphere Films

Chang Song Liu; Zhi Wen Li; Ling Wang; Zhen Xu

doi:10.4028/www.scientific.net/KEM.368-372.1374

Paper Titles

Effects of SrAl₂O₄ Homo-Buffer Layer on SrAl₂O₄:Eu Phosphors Film Grown on Glass by RF Sputtering
p.1358

Triboluminescence of SrAl₂O₄:Eu Film with Strong Adhesion Fabricated by a Combination of RF Magnetron Sputtering and Post-Annealing Treatment
p.1362

Magnetite Nanoparticles Surface Coating SiO₂ and Magnetic Properties Evaluation
p.1366

Fabrication and Characterization of Bioactive Cancellous-Like Surface on Titanium
p.1370

Rapid Reversible Superhydrophobicity to Superhydrophilicity Conversion of HF-Tuned ZnO Flower-Like Micro-Sphere Films
p.1374

Preparation of Cu Coated ZrW₂O₈ Composite Powders via Heterogeneous Precipitation Process
p.1377

On the Microstructure of Aluminum Titanate Powders Coated with Mullite Sol
p.1380

Structure and Dielectric Properties of AlN Multilayered Film on Al Substrate
p.1383

Formation of ZrO₂-Al₂O₃ Coating Layers on SiC Fiber by Dip-Coating Process
p.1386

HomeKey Engineering MaterialsKey Engineering Materials Vols. 368-372Rapid Reversible Superhydrophobicity to...

Rapid Reversible Superhydrophobicity to Superhydrophilicity Conversion of HF-Tuned ZnO Flower-Like Micro-Sphere Films

Abstract:

Superhydrophobic ZnO films were prepared by a simple low-temperature solution method, where the ZnO morphology was tuned by hydrofluoric acid. The film topography presents two different length scales: micro flower-like-spheres and nano petals. Such hierarchical structures give the film a superhydrophobic behavior with water contact angle (CA) of 151°, turning into a superhydrophilic one (CA < 5°) after 30 min vacuum ultraviolet (VUV) illumination. The transition from superhydrophobicity to superhydrophilicity is more quickly than the past report using UV illumination because VUV gives higher energy upon the ZnO films. The VUV-illuminated film can be recovered to superhydrophobic through being placed in the dark. Such special wettability can be explained based on ZnO as a photoinduced semiconductor and a photocatalyst. This study will greatly extend applications of ZnO nanomaterials to many important fields, such as microfluidic devices.