Magnetically Recyclable Nanoscale Zero-Valent Iron-Mediated PhotoRDRP in Ionic Liquid toward Smart, Functional Polymers

Tailoring Low-Polarity Ionic Liquids Using Polyhedral Oligomeric Silsesquioxane (POSS) for Advanced Polymer Hybrids

Polyhedral oligomeric silsesquioxane (POSS) can create hydrophobic spaces in various media including water-soluble networks and dendrimers. In particular, since the development of POSS ionic liquids (ILs), much effort has been devoted to investigating their thermal properties. In this manuscript, we report that POSS can create hydrophobic spaces in ILs. In comparison with a series of POSS ILs and ion pairs, we investigated the effects of the POSS core on the microenvironment around dyes in ILs by evaluating normalized polarity and Kamlet-Taft parameters with several types of solvatochromic dyes as probes. Consequently, it was revealed that POSS ILs should have low polarity where POSS could play a critical role in enhancing intermolecular interactions from the directly-connected anion to other species including cations and dyes. In terms of applications, it was found that low-polarity POSS ILs have high compatibility with conventional conjugated polymers, which can be used for fabricating highly-efficient luminescent ionic-liquid hybrid films owing to the isolation of each polymer chain by POSS even under ionic environments.

Recyclable Nano Zero-Valent Iron (nZVI)-Catalyst-Mediated Sustainable Photopolymerization of Glycidyl Methacrylate in Ionic Liquid and Functional Copolymers Thereof

Utilization of reusable catalysts and reaction media has recently been an area of interest to devise a sustainable approach. Interestingly, photoinduced reversible deactivation radical polymerization (photoRDRP) of glycidyl methacrylate (GMA) is achieved with reusable and magnetically separable nano zero-valent Iron (nZVI). This resulted in well-defined poly(glycidyl methacrylate) (PGMA) (upto 22700 g mol-1) with a low dispersity (Đ ≤ 1.20). Using an ionic liquid and a straightforward low-cost technique, three different copolymers: poly(glycidyl methacrylate-random-dimethyl amino ethyl methacrylate) poly(GMA-r-DMAEMA), poly(glycidyl methacrylate-random-methyl methacrylate) poly(GMA-r-MMA) and poly(glycidyl methacrylate-random-styrene) poly(GMA-r-St) are produced, all without the need for traditional photoinitiators. The response of the poly(GMA-r-DMAEMA) to pH variations is evaluated.

Bio-inspired hierarchical bamboo-based air filters for efficient removal of particulate matter and toxic gases

Air pollution is caused by the perilous accumulation of particulate matter (PM) and harmful gas molecules of different sizes. There is an urgent need to develop highly efficient air filtration systems capable of removing particles with a wide size distribution. However, the efficiency of current air filters is compromised by controlling their hierarchical pore size. Inspired by the graded filtration mechanisms in the human respiratory system, microporous ZIF-67 is in situ synthesized on a 3D interconnected network of bamboo cellulose fibers (BCFs) to fabricate a multiscale porous filter with a comprehensive pore size distribution. The macropores between the BCFs, mesopores formed by the BCF microfibers, and micropores within the ZIF-67 synergistically facilitate the removal of particulates of different sizes. The filtration capabilities of PM2.5 and PM0.3 could reach 99.3% and 98.6%, respectively, whereas the adsorption of formaldehyde is 88.7% within 30 min. In addition, the filter exhibits excellent antibacterial properties (99.9%), biodegradability (80.1% degradation after 14 days), thermal stability, and skin-friendly properties (0 irritation). This study may inspire the research of using natural features of renewable resources to design high-performance air-filtration materials for various applications.

Nonmetallic modified zero-valent iron for remediating halogenated organic compounds and heavy metals: A comprehensive review

Zero Valent Iron (ZVI), an ideal reductant treating persistent pollutants, is hampered by issues like corrosion, passivation, and suboptimal utilization. Recent advancements in nonmetallic modified ZVI (NM-ZVI) show promising potential in circumventing these challenges by modifying ZVI's surface and internal physicochemical properties. Despite its promise, a thorough synthesis of research advancements in this domain remains elusive. Here we review the innovative methodologies, regulatory principles, and reduction-centric mechanisms underpinning NM-ZVI's effectiveness against two prevalent persistent pollutants: halogenated organic compounds and heavy metals. We start by evaluating different nonmetallic modification techniques, such as liquid-phase reduction, mechanical ball milling, and pyrolysis, and their respective advantages. The discussion progresses towards a critical analysis of current strategies and mechanisms used for NM-ZVI to enhance its reactivity, electron selectivity, and electron utilization efficiency. This is achieved by optimizing the elemental compositions, content ratios, lattice constants, hydrophobicity, and conductivity. Furthermore, we propose novel approaches for augmenting NM-ZVI's capability to address complex pollution challenges. This review highlights NM-ZVI's potential as an alternative to remediate water environments contaminated with halogenated organic compounds or heavy metals, contributing to the broader discourse on green remediation technologies.