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1.
Int J Biol Macromol ; 270(Pt 1): 132276, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38734352

RESUMO

The reuse and development of natural waste resources is a hotspots and challenges in the research of new fiber materials and the resolution of environmental concern globally. Herein, this study aimed to develop a simple and direct manual extraction process to extract Musa core fibers (MCFs) for rapid water conduction and evaporation. Through simple processes such as ring cutting and stretching, this green and non-destructive inside-out extraction strategy enabled Musa fibers to be naturally and harmlessly degummed from natural Musa stems, with good maintenance of the fiber structure and highly helical morphology. The extracted fibers are composed of regularly and closely arranged cellulose nanofibrils in the shape of ribbon spirally arranged multi-filaments, and the single filament is about 2.65 µm. The high-purity fibers exhibit ultra-high tensile strength under a non-destructive extraction process, and the ultimate tensile strength in dry state is as high as 742.95 MPa. The tensile strength is affected by the number of fiber bundles, which shows that tensile strength and tensile modulus is higher than those of vascular bundle fibers in dry or wet condition. In addition, the MCFs membrane indicates good water conductivity, with a water absorption height of 50 mm for the sample in only 60 s. Moreover, the water evaporation rate of MCFs reaches 1.37 kg m-2 h-1 in 30 min, which shows that MCFs have excellent water conductivity and evaporation rate compared with ordinary cotton fibers. These results indicate that MCFs have great potential in replacing the use of chemical methods to extract fibers from vascular bundles, providing an effective way to achieve sustainability in quick-drying applications, as well as in the sustainable development of natural waste resources.


Assuntos
Musa , Resistência à Tração , Água , Água/química , Musa/química , Celulose/química , Nanofibras/química
2.
Mater Horiz ; 11(9): 2095-2105, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38391254

RESUMO

Solar-driven evaporation is promising to address water scarcity. However, preserving the heat inside evaporators instead of allowing run-off, and synergistically utilizing it to wick water from the bulk, is still underexplored. Herein, a dual-functional bridge of longitudinal orientated channels of Al2O3 fibers (AOFs) embedded in a multi-layered nonwoven evaporator was proposed to create a buffer for spontaneous thermal conduction and anti-gravitational water pumping. As a self-floating system with high porosity and flexibility, benefiting from the strong water transporting ability and high thermal conductivity of the AOFs, a superhigh evaporation rate (2.79 kg m-2 h-1 under 1 sun) can be achieved with great stability and durability. This work highlights the potential of promoting thermal management using a large-scale vapour chamber and mass-producible nonwoven technology to prepare a high-performance evaporator for practical applications.

3.
Adv Sci (Weinh) ; 11(4): e2306711, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38041500

RESUMO

The development of conversion-typed anodes with ultrafast charging and large energy storage is quite challenging due to the sluggish ions/electrons transfer kinetics in bulk materials and fracture of the active materials. Herein, the design of porous carbon nanofibers/SnS2 composite (SnS2 @N-HPCNFs) for high-rate energy storage, where the ultrathin SnS2 nanosheets are nanoconfined in N-doped carbon nanofibers with tunable void spaces, is reported. The highly interconnected carbon nanofibers in three-dimensional (3D) architecture provide a fast electron transfer pathway and alleviate the volume expansion of SnS2 , while their hierarchical porous structure facilitates rapid ion diffusion. Specifically, the anode delivers a remarkable specific capacity of 1935.50 mAh g-1 at 0.1 C and excellent rate capability up to 30 C with a specific capacity of 289.60 mAh g-1 . Meanwhile, at a high rate of 20 C, the electrode displays a high capacity retention of 84% after 3000 cycles and a long cycle life of 10 000 cycles. This work provides a deep insight into the construction of electrodes with high ionic/electronic conductivity for fast-charging energy storage devices.

4.
ACS Omega ; 8(44): 41765-41772, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37970027

RESUMO

TiO2 has been widely used in photodegradation of pollutants, but it suffers from inferior photocatalytic performance under solar light illumination. Thus, novel porous ZnTiO3/TiO2 heterostructured photocatalysts are constructed by hydrothermal and carbonization techniques using ZIF-8 as a sacrificial template. After coating with TiO2, ZIF-8 nanocubes are selectively etched and subsequently coprecipitated with Ti ions during the hydrothermal process. Thereafter, the pores generated from carbonized ZIF-8 provide a large specific surface area and abundant active reaction sites for photocatalysis after annealing, producing stable ZnTiO3/TiO2 nanocomposites. Thus, porous ZnTiO3/TiO2 heterostructured photocatalysts exhibit excellent photocatalytic performance under solar light irradiation due to the boosted electron-hole separation/transfer. The kinetic constant of ZnTiO3/TiO2 nanocomposites (4.66 × 10-1 min-1) is almost 100 and 3.7 times higher than that of self-degradation (4.69 × 10-3 min-1) and TiO2 (1.27 × 10-1 min-1), respectively. This facile strategy provides a deep insight into synthesizing heterostructured photocatalysts with high efficiency in the field of environmental remediation.

5.
RSC Adv ; 13(44): 30898-30904, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37869382

RESUMO

The proliferation and differentiation of bone mesenchymal stem cells (BMSCs) in vitro are the key properties of bone tissue engineering for biomaterials. In this study, hydroxyapatite (HA) coated porous carbon nanofibres (PCNFs) were prepared to load dexamethasone (DEX) and further improve the differentiation ability of the BMSCs. Various characterisations were applied to reveal the DEX loading efficacy and biocompatibility, especially the differentiation strength. The results showed that HA could be successfully coated on the PCNFs by pretreating the surface using PEG conjugation. With an increase of HA, the particle diameter increased and the DEX loading decreased. In vitro experiments proved higher cell viability, alkaline phosphatase (ALP) activity, calcium nodule secretion ability and the RUNX2 protein expression, indicating that the as-prepared was of great biocompatibility and optimised osteoconductivity, which was attributed to the componential imitation to natural bone and the accelerated BMSCs differentiation. Consequently, the novel DEX loaded and HA coated PCNFs can provide potential applications in bone tissue regeneration.

6.
Gels ; 9(8)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37623054

RESUMO

As an important inorganic material, alumina ceramic nanofibers have attracted more and more attention because of their excellent thermal stability, high melting point, low thermal conductivity, and good chemical stability. In this paper, the preparation conditions for alumina spinning gel, such as the experimental raw materials, spin finish aid, aging time, and so on, are briefly introduced. Then, various methods for preparing the alumina ceramic nanofibers are described, such as electrospinning, solution blow spinning, centrifugal spinning, and some other preparation processes. In addition, the application of alumina ceramic nanofibers in thermal insulation, high-temperature filtration, catalysis, energy storage, water restoration, sound absorption, bioengineering, and other fields are described. The wide application prospect of alumina ceramic nanofibers highlights its potential as an advanced functional material with various applications. This paper aims to provide readers with valuable insights into the design of alumina ceramic nanofibers and to explore their potential applications, contributing to the advancement of various technologies in the fields of energy, environment, and materials science.

7.
RSC Adv ; 13(27): 18480-18487, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37346944

RESUMO

Water pollution caused by the continuous development of industrialization has always been a common concern of mankind. Herein, a novel strategy to fabricate a high-performance composite membrane based on dual-network structured nonwoven net/UHMWPE nanopores via a thermal phase separation and composite technique is reported. By thermal phase separation of ultra-high-molecular weight polyethylene (UHMWPE)/liquid paraffin (LP), this approach enables 3D nanopores to tightly bond with a nonwoven net to form a dual-network structure. The dual-network composite membrane possesses the integrated features of pore structure and high porosity (89.9%). After modification with hyperbranched polymers (HBPs), the composite membrane with the desirable surface chemistry achieves high-efficiency filtration (water flux = 1054 L m-2 h-1, rejection rate = 50 nm PS nanospheres almost close to 100%, and antibacterial properties). The fabrication of such composites may provide new insights into the design and development of high-performance filtration and separation materials for various applications.

8.
Chem Commun (Camb) ; 59(56): 8743-8746, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37358034

RESUMO

Hierarchical Mn-Ni2P/NiFe LDH arrays were developed as a self-supported electrode. Because of the synergistic effect and self-supported structure, it presents brilliant bifunctional catalytic activities for the HER and UOR. Surprisingly, the voltage of a urea electrolytic cell coupling the HER with the UOR was as low as 1.494 V at 10 mA cm-2.

9.
RSC Adv ; 12(52): 34107-34116, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36544997

RESUMO

PVDF/ZnO/CuS photocatalysts with ZnO/CuS heterojunctions were synthesized via electrospinning, hydrothermal, and ion-exchange techniques. As matrix materials, electrospun PVDF nanofibers are easy to be recycled and reused. ZnO nanorods anchored on PVDF nanofiber with high specific surface area provide abundant active reaction sites for photocatalysis. While the loaded CuS nanoparticles as a photosensitizer compensate the low quantum efficiency of ZnO and improve the visible-light photocatalytic efficiency. As a result, the PVDF/ZnO/CuS composited photocatalyst exhibits outstanding photocatalytic performance in exposure to UV and visible light owing to the suppressed recombination of electron-hole pairs and widened visible light absorption range. The kinetic constants of PVDF/ZnO/CuS nanocomposites under UV irradiation (9.01 × 10-3 min-1) and visible light (6.53 × 10-3 min-1) irradiation were 3.66 and 2.53 times higher than that of PVDF/ZnO (2.46 × 10-3 min-1 & 2.58 × 10-3 min-1), respectively. Furthermore, PVDF/ZnO/CuS nanocomposites demonstrate excellent robustness in terms of recycling and reuse, which is advantageous in practical applications.

10.
ACS Omega ; 7(2): 2198-2204, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35071907

RESUMO

To improve the adsorption performance of carbon materials, novel ZnO nanoparticle-incorporated porous carbon nanofibers (Zn@PCNFs) were prepared via an electrospinning technique. A facile one-step fabrication strategy was proposed to simultaneously complete the carbonization of a peroxided polyacrylonitrile framework, the activating treatment caused by ZnO reducing to Zn, and the pore generation caused by evaporation of reduced Zn with a low melting point. The influences of the pH, ion category, and concentration on methylene blue adsorption were investigated. The physical-chemical characterizations showed that ZnO was homogeneously distributed on the nanofibers and micropores were generated. The adsorption results revealed that an efficient adsorption was obtained within a large range of pH values through different adsorption models, which was accelerated by increasing the temperature. Therefore, the novel Zn@PCNFs are anticipated to be applied in the future as an effective dye waste adsorbent.

11.
Nanomaterials (Basel) ; 11(9)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34578717

RESUMO

To improve the bone regeneration ability of pure polymer, varieties of bioactive components were incorporated to a biomolecular scaffold with different structures. In this study, polysilsesquioxane (POSS), pearl powder and dexamethasone loaded porous carbon nanofibers (DEX@PCNFs) were incorporated into polylactic (PLA) nanofibrous scaffold via electrospinning for the application of bone tissue regeneration. The morphology observation showed that the nanofibers were well formed through electrospinning process. The mineralization test of incubation in simulated body fluid (SBF) revealed that POSS incorporated scaffold obtained faster hydroxyapatite depositing ability than pristine PLA nanofibers. Importantly, benefitting from the bioactive components of pearl powder like bone morphogenetic protein (BMP), bone mesenchymal stem cells (BMSCs) cultured on the composite scaffold presented higher proliferation rate. In addition, by further incorporating with DEX@PCNFs, the alkaline phosphatase (ALP) level and calcium deposition were a little higher based on pearl powder. Consequently, the novel POSS, pearl powder and DEX@PCNFs multi-incorporated PLA nanofibrous scaffold can provide better ability to enhance the biocompatibility and accelerate osteogenic differentiation of BMSCs, which has potential applications in bone tissue regeneration.

12.
Polymers (Basel) ; 12(3)2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32143481

RESUMO

In this study, a facile and effective method is adopted to prepare mechanochemically robust super antifouling membrane surfaces. During the process, vinyl trimethoxy silane (VTMS) was used as the reactive intermediate for coupling the hydrophilic inorganic SiO2 nanoparticle layer on to the organic ultra-high-molecular-weight polyethylene (UHMWPE) membrane surface, which created hierarchical nanostructures and lower surface energy simultaneously. The physical and chemical properties of the modified UHMWPE composite membrane surface were investigated. FTIR and XPS showed the successful chemical grafting of VTMS and SiO2 immobilization, and this modification could effectively enhance the membrane's surface hydrophilicity and filtration property with obviously decreased surface contact angle, the pure water flux and bovine serum albumin (BSA) rejection were 805 L·m-2·h-1 and 93%, respectively. The construction of the hydrophilic nano-SiO2 layer on the composite membrane surface for the improvement of membrane antifouling performance was universal, water flux recovery ratio values of BSA, humic acid (HA), and sodium alginate (SA) were all up to 90%. The aim of this paper is to provide an effective approach for the enhancement of membrane antifouling performance by the construction of a hydrophilic inorganic layer on an organic membrane surface.

13.
ACS Omega ; 5(2): 986-994, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31984254

RESUMO

Bioinspired superhydrophobic surfaces have attracted great interest due to their special functions and wide applications. However, it is still a big challenge to construct a durable superhydrophobic coating for large-scale applications due to its easy destruction by the mechanochemical attack. In this mini-review, we present the state-of-the-art developments in the rational design of mechanochemical durable and self-healing superhydrophobic surfaces. First, the mechanically durable superhydrophobic surfaces are constructed to endure mechanical damage by adjusting the surface morphology and increasing the binding force between the substrates and the modified materials. Second, chemical damages also have been taken into consideration to develop chemically robust superhydrophobic surfaces, such as chemical etching, ultraviolet (UV)-light irradiation, and bioerosion, etc. Third, endowing superhydrophobic coatings with self-healing function can effectively improve the durability and prolong the lifespan of the coatings by releasing low-surface-energy agents or regenerating topographic structures. Finally, the challenges and future perspectives in developing super durable bioinspired superhydrophobic surfaces by structure design and chemistry control are discussed. The innovative points provided in this mini-review will provide deep fundamental insight for prolonging the lifetime of the superhydrophobic surfaces and enable their practical applications in the near future.

14.
Nanoscale Res Lett ; 13(1): 379, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30470923

RESUMO

In this paper, a simple method to prepare hydrophilic reduced graphene oxide (rGO) was proposed via reducing GO by amino-terminated hyperbranched polymer (NHBP), the as-prepared NrGO could present excellent dispersibility, near infrared (NIR) light absorbance, photothermal conversion ability and stability. Then, the doxorubicin hydrochloride (DOX) was conjugated with NrGO to prepare the drug-loading system, and a pH/photothermal dual-responsive drug delivery behavior was characterized. At acidic environment or under NIR laser irradiation, the drug release rate could be improved, which is beneficial to control release anti-tumor drug in tumor tissues. What is more, the in vitro cell experiments revealed that NrGO was well biocompatible, and in the tumor inhibition part, comparing to the control group without any treatment, DOX@NrGO gained efficient chemo-photothermal synergetic therapy, the inhibition rate of which was much higher than single chemotherapy of released DOX. Therefore, the as-prepared DOX@NrGO obtained great potential application in tumor therapy and an excellent candidate in other biomed applications.

15.
Molecules ; 23(10)2018 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-30301225

RESUMO

A co-based porous metal-organic framework (MOF) of zeolitic imidazolate framework-67 (ZIF-67) and carbon nanofibers (CNFs) was utilized to prepare a ZIF-67/CNFs composite via a one-pot synthesis method. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) were employed to investigate the morphology, structure, and composition of the resulting composite. A novel high-performance non-enzymatic electrochemical sensor was constructed based on the ZIF-67/CNFs composite. The ZIF-67/CNFs based sensor exhibited enhanced electrocatalytic activity towards H2O2 compared to a pure ZIF-67-based sensor, due to the synergistic effects of ZIF-67 and CNFs. Meanwhile, chronoamperometry was utilized to explore the detection performance of the sensor. Results showed the sensor displayed high-efficiency electrocatalysis towards H2O2 with a detection limit of 0.62 µM (S/N = 3), a sensitivity of 323 µA mM-1 cm-2, a linear range from 0.0025 to 0.19 mM, as well as satisfactory selectivity and long-term stability. Furthermore, the sensor demonstrated its application potential in the detection of H2O2 in food.


Assuntos
Técnicas Biossensoriais , Peróxido de Hidrogênio/isolamento & purificação , Estruturas Metalorgânicas/química , Nanofibras/química , Carbono/química , Peróxido de Hidrogênio/química
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