Fabrication of superhydrophobic and UV-resistant surface on cotton fabric via layer-by-layer assembly of silica-based UV absorber

Application of nanosilica in the construction industry: A bibliometric analysis using Methodi Ordinatio

The number of publications related to the implementation of nanotechnology in the construction industry, and specifically to the application of nanosilica (SiO2), has had a constant increase in recent years. Based on this, in the present work, an analysis was carried out using bibliometric techniques, with the aim at characterizing the development of specialized literature and identifying the largest areas of growth in the field, maintaining hydrophobic nanosilica as the research guideline. This analysis acquired information from the Scopus and Web of Science (WoS) databases to compare bibliometric indicators of the publications. It should be noted that, even though bibliometric analysis is useful to identify the study areas of greatest interest, to complement this work, the implementation of a method that helped in the research process to obtain the most important bibliography was required. This study implemented Methodi Ordinatio, which helped to take a new direction. Therefore, based on this method, a list of articles cataloged and ranked is obtained, which is the basis for integrating the final bibliographic portfolio. •The study applies the Methodi Ordinatio to obtain a portfolio of the most relevant articles to guide the researchers' work.•Insightful information can be obtained using VOSviewer to analyze and visualize metadata of the bibliographic portfolio.•The study demonstrates how the alpha value in the InOrdinatio formula modifies the resulting portfolio.

Fabrication of Robust Superhydrophobic Nickel Films on Steel Surface With High Corrosion Resistance, Mechanical and Chemical Stability

Superhydrophobic films were successfully grafted on a steel substrate using potentiostatic electrodeposition of nickel followed by treatment with myristic acid (MA) as a low surface energy material. A scanning electron microscope (SEM) was used to investigate the surface topography of the prepared superhydrophobic films. The results revealed that the prepared Ni films modified by myristic acid have micro-nano structures. Fourier transform infrared spectrophotometer (FTIR) and X-ray diffraction (XRD) measurements showed that the steel substrate was coated with nickel film modified with myristic acid. Three different nickel films were prepared: the Ni-MA (I) deposited from pure nickel sulfate bath (1.0 M NiSO4), Ni-MA (II) deposited from pure nickel chloride bath (1.0 M NiCl2. 6H2O), and the third Ni-MA (III) film deposited from Watts bath (0.2 M NiCl2. 6H2O and 0.8M NiSO4). The superhydrophobic Ni-MA (I) film has the highest corrosion resistance, chemical stability, and mechanical abrasion resistance, while Ni-MA (II) film has the lowest properties.

Preparation and Properties of Hydrophobically Modified Nano-SiO2 with Hexadecyltrimethoxysilane

As a common inorganic silicon material, nano-SiO₂ is extremely hydrophilic due to the presence of a large number of hydroxyl groups on its surface, which limits its application in some fields. In this research, hexadecyltrimethoxysilane (HDTMS) was used to modify nano-SiO₂, and the results of water contact angle (WCA), Fourier transform infrared (FTIR), two-dimensional correlation spectroscopy (2D-COS), thermogravimetric (TG) analysis, and scanning electron microscopy (SEM) indicated that the hydrophobic long-chain alkyl of HDTMS was successfully grafted onto the surface of nano-SiO₂. When the ratio of nano-SiO₂ and HDTMS was 0.25:1, the WCA of nano-SiO₂ modified with HDTMS (HDTMS-nano-SiO₂) reached 170.9°, which was about 5.62 times higher than that before modification, and the superhydrophobic property was obtained. The novelty of this work lies in the modified nano-SiO₂ with a WCA of over 170° and the analysis of the modification mechanism with the help of 2D-COS. This study can provide a reference for the hydrophobic modification of nano-SiO₂ and its application field expansion.

Environmental effects of stratospheric ozone depletion, UV radiation, and interactions with climate change: UNEP Environmental Effects Assessment Panel, Update 2020

This assessment by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) provides the latest scientific update since our most recent comprehensive assessment (Photochemical and Photobiological Sciences, 2019, 18, 595-828). The interactive effects between the stratospheric ozone layer, solar ultraviolet (UV) radiation, and climate change are presented within the framework of the Montreal Protocol and the United Nations Sustainable Development Goals. We address how these global environmental changes affect the atmosphere and air quality; human health; terrestrial and aquatic ecosystems; biogeochemical cycles; and materials used in outdoor construction, solar energy technologies, and fabrics. In many cases, there is a growing influence from changes in seasonality and extreme events due to climate change. Additionally, we assess the transmission and environmental effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for the COVID-19 pandemic, in the context of linkages with solar UV radiation and the Montreal Protocol.

Robust Microcapsules with Durable Superhydrophobicity and Superoleophilicity for Efficient Oil-Water Separation

The poor ultraviolet (UV) resistance and insufficient solvent compatibility are challenges for long-term storage and service of oil-water separation materials in practical applications. Herein, a superhydrophobic/superoleophilic surface with nano- to microscale hierarchical structures was formed spontaneously on robust microcapsules (MCs) via in situ polymerization and a sol-gel surface treatment. The resultant MCs possessed superior UV-resistant and solvent-proof superhydrophobicity. The water contact angles (WCAs) of the MC coating remained above 160° and the sliding angles (SAs) were below 3° after 9 days of UV aging test or 20 days of nonpolar and polar aprotic solvent immersion tests. More interestingly, these MCs can be used to separate the oil phase from its aqueous emulsion effectively, achieving a high and reusable separation efficiency with over 90% oil purity after 10 cycles of filtrations even after 13 days of UV aging. Therefore, these novel MCs will exhibit effective oil-water separation performance, superior chemical stability, outstanding reusability, and long-term storage stability for promising practical applications.