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Serious water contamination induced by massive discharge of cadmium(II) ions is becoming an emergent environmental issue due to high toxicity and bioaccumulation; thus, it is extremely urgent to develop functional materials for effectively treating with Cd2+ from wastewater. Benefiting from abundant binding sites, simple preparation process, and adjustable structure, UiO-66-type metal-organic frameworks (MOFs) had emerged as promising candidates in heavy metal adsorption. Herein, monolithic UiO-66-(COOH)2-functionalized cellulose fiber (UCLF) adsorbents were simply fabricated by incorporating MOFs into cellulose membranes through physical blending and self-entanglement. A two-dimensional structure was facilely constructed by cellulose fibers from sustainable biomass agricultural waste, providing a support platform for the integration of eco-friendly UiO-66-(COOH)2 synthesized with lower temperature and toxicity solvent. Structure characterization and bath experiments were performed to determine operational conditions for the maximization of adsorption capacity, thereby bringing out an excellent adsorption capacity of 96.10 mg/g. UCLF adsorbent holding 10 wt % loadings of UiO-66-(COOH)2 (UCLF-2) exhibited higher adsorption capacity toward Cd2+ as compared to other related adsorbents. Based on kinetics, isotherms, and thermodynamics, the adsorption behavior was spontaneous, exothermic, as well as monolayer chemisorption. Coordination and electrostatic attraction were perhaps mechanisms involved in the adsorption process, deeply unveiled by the effects of adsorbate solution pH and X-ray photoelectron spectroscopy. Moreover, UCLF-2 adsorbent with good mechanical strength offered a structural guarantee for the successful implementation of practical applications. This study manifested the feasibility of UCLF adsorbents used for Cd2+ adsorption and unveiled a novel strategy to shape MOF materials for wastewater decontamination.
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Designing of a green and multifunctionally integrated cellulose-based flexible wearable material with personal thermoregulation, water and ultraviolet (UV) resistance is essential for the development of personal thermal management and smart textiles. Herein, a hydrophobic silver nanoparticles cellulose-based membrane (H-AgNPs/CEPCM) was prepared through simple solution blending, spin-coating process and chemical vapor modification. The prepared membrane exhibited excellent UV resistance due to the synergistic effect of carbon quantum dots (CQDs) as well as UV-absorbing functional groups. The spin-coated AgNPs layer with high infrared reflectivity has great radiant insulation, and temperature was reduced by 3.4 °C compared with H-CEPCM in indoor environment. Furthermore, the mechanical properties of H-AgNPs/CEPCM were significantly improved by the introduction of amide and ether bonds, as well as a large number of hydrogen bonds. This led to a tensile strength of 23.21 MPa and an elongation at break of 16.57 %, while also providing water resistance. Additionally, the H-AgNPs/CEPCM exhibited outstanding thermal stability and hydrophobicity. This work may provide a feasible and promising strategy for the construction of multifunctional integrated cellulose membrane materials for radiant insulation, outdoor textiles and novel UV protection applications.
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Developing rational sorbent for viscous crude oil clean-up is still a daunting challenge, which requires rapid oil-uptake capability and scalable fabrication process. Herein, a heatable hydrophobic sponge sorbent (H-MXene/PVA/MS) with excellent light/Joule-heating performances was fabricated by a simple and feasible top-down approach. MXene nanosheets firmly coated on the substrate skeleton gave the sorbent outstanding ability to convert solar/electricity into heat rapidly due to the localized surface plasmon resonance (LSPR) effect and ultrahigh metallic conductivity. The surface temperature of H-MXene/PVA/MS could reach about 80 â under 1.0 sun irradiation within 30 s and 125 â under a low applying voltage of 6 V within 25 s. The rapid and sufficient heat generation on the sorbent would effectively warm the surrounding oil and accelerate its absorption. The oil absorption rate under 1.0 sun irradiation (1 kW/m2) improved about 41.5 times compared to the unheated sorbent. Moreover, the sorbent showed practical application potential in harsh environments due to its high coating firmness, durability, elasticity, and suitability for large-scale production and operations. Thus, the easily-prepared H-MXene/PVA/MS sorbent, which mainly focuses on solar-heating, supplemented by Joule-heating, provides an efficient and energy-efficient strategy for addressing large-scale viscous oil spill clean-up.
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Developing self-heating sorbents for rapid clean-up of viscous oil spills by using clean solar energy is attracting attention. Still, simple and scalable fabrication approaches of solar-heating sorbents remain challenging. Herein, a facile and practical modification strategy was presented to develop a solar-heating modified melamine sponge (rGO/CNT/MS) by dip-coating layer-by-layer (LBL) electrostatic assembly of GO and CNT with opposite charges onto MS skeleton followed by thermal reduction, without any complicated microfabrication and hydrophobic modification processes. Based on the intercalation of CNT into rGO layers and strong conjugation/hyperconjugation synergy of rGO and CNT, the light sorption ability, photothermal conversion, hydrophobicity and mechanical properties of the rGO/CNT/MS sorbent were further improved compared to rGO/MS and CNT/MS. The surface temperature could reach 75 â in 100 s under 1 sun radiation (1 kW m-2), which would effectively absorb crude oil by in-situ sunlight-heating to reduce its viscosity. The sorption speed increased by about 30 times compared with no sunlight irradiation, and the continuous sorption capacity was up to 1.71 g/cm2 at 610 s driven by pump force. The easily-prepared solar-assisted rGO/CNT/MS with high photothermal performance, corrosion resistance, mechanical compressibility, coating firmness and oil sorption ability showed huge potential application in oil spill recovery.
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Petróleo , Grafito , Calefacción , Interacciones Hidrofóbicas e Hidrofílicas , Triazinas , Viscosidad , Agua/químicaRESUMEN
Fabrication of simple and efficient adsorbents is greatly vital to satisfy the requirements of removal of tellurium in wastewater treatment, yet remains challenging. Here, a facile and cost-effective strategy to develop ZIF-L coated self-crosslinking cellulose membrane (ZIF-L/SC membrane) for tellurium adsorption was presented. In-situ vertical growth of ZIF-L nanoplates with functional properties on membrane substrate is an available strategy, effectively remedying deficiency of pure nanosized sorbent in agglomeration problem and unhandy recovery. The SC membrane formed by strong hydrogen bonding among cellulose fibers is an excellent substrate, due to the favorable mechanical strength and abundant hydroxyl groups. The as-prepared ZIF-L/SC membrane shows advantageous morphology of large contact surface, fine thermal stability and eligible mechanical strength. The adsorption performance and possible mechanism of ZIF-L/SC membrane for Te (IV) were investigated by diverse characterization methods, showing admirable adsorption effect. Furthermore, the ZIF-L/SC membrane has excellent antibacterial properties, thus it is expected to deal with membrane fouling caused by microorganism breeding. Therefore, the bifunctional ZIF-L/SC membrane with excellent antibacterial activity is anticipated to be a promising candidate for efficient tellurium adsorbents, and simultaneously have potential in various fields in the future.
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Zeolitas , Adsorción , Antibacterianos/farmacología , Celulosa , TelurioRESUMEN
Due to the variety of oily wastewater and complexity of separation system, it has put forward new challenge and requirement to separation materials for on-demand separation of various oil/water mixtures. Here, we reported a facile waste-to-resource strategy to rationally fabricate hierarchical ZnO nanopillars coating onto the surface of waste brick grains (ZnO/WBG) via simple physical process and in-situ growth technique. Specifically, the directly as-prepared ZnO/WBG possess superhydrophilic/underwater superoleophobic (UWSOB) properties and modified ZnO/WBG by organosilicon reagent possess quasi superhydrophobic/superoleophilic (SHOBI) properties. It is also worth noting that this discrete ZnO/WBG with opposite wettability can be accumulated into ZnO/WBG layer with numerous tortuous channel structure, making it feasible for on-demand separating various oil/water mixtures whether immiscible light- and heavy-oil/water mixtures or oil-in-water and water-in-oil emulsions. It has been demonstrated that the filter layers with opposite wettability exhibit high separation efficiency and flux, excellent chemical stability and admirable recyclability. Thus, this novel and cost-effective ZnO/WBG layer holds great promise for large-scale and versatile oil/water separation. Additionally, this work presents a sustainable perspective of effectively utilizing waste brick to construct workable functionalized materials with tremendous application potential, showing far-reaching value and significance in fundamental research and environmental protection.
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Purificación del Agua/métodos , Emulsiones , Interacciones Hidrofóbicas e Hidrofílicas , Aceites/química , Aguas Residuales , Agua/química , HumectabilidadRESUMEN
Outdoor cold stress often causes an undesired threat to public health, but devising an efficient strategy to achieve localized outdoor warming of the human body is still a great challenge. Polar bear pelt can absorb sunlight and reflect thermal radiation generated inside the body, which helps in adapting to the cold environment. Inspired by the radiation control strategy of the polar bear pelt, this study reports a porous Ag/cellulose/carbon nanotube (CNT)-laminated nanofiber membrane, in which one side of the cellulose basement membrane is coated with CNTs using a foam finishing process and the Ag layer is deposited on the other side by magnetron sputtering. Based on the high solar radiation absorptivity from CNT coating and the high infrared radiation reflectivity from Ag coating, the biomimetic membrane provides radiation warming by maximizing the heat input from the sun and minimizing the human radiation heat output. Because of excellent electrical conductivity, the Ag layer can work as a wearable heater to induce fast thermal response and uniform electroheating for extra warmth under a low supplied voltage. Moreover, the biomimetic membrane possesses porosity, hydrophilicity, breathability, flexibility, and mechanical stability, suggesting its huge potential for outdoor personal thermal management. Because of their versatility, the applications of the biomimetic membranes may be extended to wearable electronics, smart garments, and thermal control materials.
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Materiales Biomiméticos/química , Calor , Membranas Artificiales , Nanofibras/química , Pelaje de Animal , Animales , Diseño de Equipo , Rayos Infrarrojos , Nanotubos de Carbono/química , Plata/química , Luz Solar , UrsidaeRESUMEN
Waste brick (WB), as a major type of construction and demolition waste, has posed much potential disasters to the environment and society due to the main disposal method of direct landfill. In this work, we presented a sustainable and promising recycling approach to transform WB into TiO2 nanoneedles functionalized waste brick grain material (TiO2/WBG) via a simple physical treatment and in-situ growth technique. The raw WBG can be as promising substrate material due to excellent chemical stability. After surface functionalization of TiO2 nanoneedles, the obtained TiO2/WBG exhibits significantly enhanced hierarchical porous structure. Based on the inherent chemical properties and hierarchical structure of TiO2 nanoneedles coating, TiO2/WBG shows special wettability of excellent underwater oleophobicity and photodegradability of organic pollutants. Besides, the modified TiO2/WBG with low-surface-energy chemical obtains fine hydrophobicity. Therefore, the as-prepared TiO2/WBG is believed to hold potential applications in oil/water separation, pollutant degradation and water purification. This work opens new avenues for effectively utilizing waste brick as resource to fabricate functionalized material with potential application value, showing far-reaching value and significance in fundamental research and environmental protection.
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To maintain personal thermal comfort in cold weather, indoor heating consumes large amount of energy and is a primary source of greenhouse gas emission. Traditional clothes are too thick for thermal comfort in cold outdoor environment, resulting the lower wearing comfort. In this work, a multifunctional Ag nanoparticles/cellulose fibers thermal insulation membrane starting from waste paper cellulose fibers was prepared via simple silver mirror reaction and subsequent vacuum filtration process to improve the infrared reflection properties of membranes for human thermal insulation. The sphere-like Ag nanoparticles were tightly anchored on surface of waste paper cellulose fibers, forming an Ag nanoparticles infrared radiation reflection coating with high infrared reflectance, resulting in high thermal insulation capacity of the thermal insulation membrane. In addition, Ag nanoparticles endow the thermo insulation membrane with excellent antibacterial activity, and the thermo insulation membranes can effectively inhibit the growth of both Staphylococcus aureus and Escherichia coli. In this thermal insulation system, the thermo insulation membranes show superhydrophilicity and porosity, which allow the membranes to be breathable for comfortable wearing feeling. These promising results including high infrared reflection for high thermal insolating, high breathability for wearing comfort, and excellent antibacterial activity make the Ag/cellulose thermo insulation membranes promising candidates for applications in human thermal management, energy regulation and other facilities.