Hydrophilicity and Hydrophobicity Control of Plasma‐Treated Surfaces via Fractal Parameters

Abstract

It is still problematic to define a direct relationship between specific properties of a nanostructured surface (e.g., wettability) and its morphology. Not surprisingly, scientists continue to explore en masse the cut‐and‐try method. In this work, new insights are presented into the correlation of functional properties of the complex nanocomposites with their morphological characteristics. Using polyethylene‐terephthalate (PET) as a model material due to its importance and wide use in experiments, super‐hydrophilic nanocomposites amenable to be used in a variety of industrial applications are first developed, by exposing PET samples to oxygen plasma under controlled conditions. The morphology of the surfaces is confirmed using AFM and SEM techniques, and wettability in air and its oleophobic properties in water using contact angle and roll‐off measurements. Next, different analytical tools such as Minkowski connectivity (Euler‐Poincaré characteristic), Hough distributions and 2D FFT are applied to study ordering, connectivity, and fractal characteristics of the samples. It is concluded that fractal dimension, along with ordering and connectivity, are among the major characteristics of the nanocomposite that determine many important physical and chemical properties of the functional nanomaterials, and the fractal dimension could be a target morphological feature to inform the design of fabrication technology.

Hierarchical Carbon Nanocone-Silica Metamaterials: Implications for White Light Photoluminescence

“…Therefore, a downshift of G peak on 6 cm −1 relates to phonon quantum confinement effect but not to amorphization of the nanostructures. 43 This fact is also supported by the relation I (D) /I (G) = 1.03 for 03A sample, and sp 2 sites convert to sp 3 . Composition of the layers was characterized by X-ray diffraction (XRD), using the Rigaku SmartLab diffractometer, Cu−Kα radiation from 9 kW X-ray tube with a rotating anode.…”

“…Intelligent design of structurally complex hierarchical metamaterials remains a significant scientific and engineering challenge. Yet, these materials and in particular metamaterials based on carbonous nanostructured materials are becoming increasingly important for the advancement of numerous fields. − These range from optoelectronic , and photoelectrochemical devices, photocatalysts, , sensors, photodiodes, single-photon light sources, and single-photon emitters to various vertical graphene-based devices, integrated photonic devices, and environmental applications . Metamaterials also play an increasingly critical role in advancing space tech-focused applications with photon-active diamond films used for the photonic space propulsion and nanostructured emitters for plasma propulsion systems , with both technologies critical for miniaturized space assets. , …”

Functional Nanomaterials from Waste and Low‐Value Natural Products: A Technological Approach Level

“…The latter could potentially be the most important descriptor to predict and hence control the surface properties. [ 3 ] Such a deep level of controllability of the nanomaterial properties has been achieved by application of highly reactive plasma environments. Figure illustrates the fractal dimensions estimated for the set of samples resulting from this experiment, as well as 3D objects that display similar fractal properties, including an Apollonian sphere and 3D Von Koch.…”

“…Reproduced with permission. [ 3 ] Copyright 2021, Wiley. The images of Menger sponge and Von Koch objects are reprinted under conditions of Creative Commons licenses.…”

Controlled Deposition of Nanostructured Hierarchical TiO2 Thin Films by Low Pressure Supersonic Plasma Jets

“…This is because of their wide range of available chemistries, different shapes of varying sizes, large surface-to-bulk ratios, and quantum-confinement effects at small length scales. Metallic and metal oxide nanoparticles and their thin films play particularly important roles in the advancement [ 1 , 2 ] of sensors [ 3 , 4 , 5 ], photocatalysts [ 6 , 7 ], bio-electronic-based devices [ 8 , 9 ], super-hydrophobic and self-cleaning materials [ 10 , 11 ], and various nanoelectronic devices [ 12 , 13 ]. In addition, light-sensitive diamond films have found applications in space technology [ 14 ], while other types of nanostructured aggregates are promising for the achievement of propulsion systems based on plasma technologies [ 15 , 16 ].…”