Stable Superwetting Surface Prepared with Tilted Silicon Nanowires

Abstract

Large-scale uniform nanostructured surface with superwettability is crucial in both fundamental research and engineering applications. A facile and controllable approach was employed to fabricate a superwetting tilted silicon nanowires (TSNWs) surface through metal-assisted chemical etching and modification with low-surface-energy material. The contact angle (CA) measurements of the nanostructured surface show a large range from the superhydrophilicity (the CA approximate to 0°) to superhydrophobicity (the CA up to 160°). The surface becomes antiadhesion to water upon nanostructuring with a measured sliding angle (α) close to 0°. Moreover, the fluorinated TSNWs surface exhibits excellent stability and durability because strong chemical bonding has been formed on the surface.Graphical Abstract

Silicon nanowire array overcomes chemotherapeutic resistance by inducing the differentiation of breast cancer stem cells

“…The data demonstrated that compared to the Si wafer, the SiNWA tended to better wet. This observation can be explained in terms of the morphology of SiNWA: the nanostructure of the surface increases its contact area with water, which makes the surface more hydrophilic 35 . To investigate the effects of surface chemical properties on the hydrophilic/hydrophobic, we investigated the elements on the surface of SiNWAs by X‐ray photoelectron spectroscopy (XPS).…”

“…This observation can be explained in terms of the morphology of SiNWA: the nanostructure of the surface increases its contact area with water, which makes the surface more hydrophilic. 35 To investigate the effects of surface chemical properties on the hydrophilic/hydrophobic, we investigated the elements on the surface of SiN-WAs by X-ray photoelectron spectroscopy (XPS). As shown in Figure 1F, XPS of the silicon peaks revealed the changes at the surface of wafer and SiNWAs.…”

Grazing incidence X-ray diffraction measurement of silver nanoparticles in metal-assisted etching of silicon

“…Before etching, the silicon wafers were cleaned by toluene, acetone, ethanol, and H 2 O sequentially, followed by immersion in the mixture of H 2 O 2 :H 2 SO 4 (1:3 volume ratios) for 10 min; and then thoroughly rinsed and placed in the deionized water before drying with nitrogen gas. The etching procedure to achieve SiNWs is composed of two steps: in Step 1, the wafers were directly introduced into a mixture of 4.8 M HF and 2, 3, 4, and 8 mM AgNO 3 for 1 min for silver depositing on the surface; in Step 2, the resulting samples were immersed in an etching solution of 4.8 M HF and 0.2 M H 2 O 2 for 30 min, followed by the deionized water rinsing and drying with nitrogen (Meng et al ., 2016). These samples were labeled with the AgNO 3 concentration prepared, e.g.…”