Offshore oil spills, industrial oily wastewater, and domestic oil pollution are some of the most serious global challenges, and are leading environmental causes of morbidity and mortality. Nanofiber ...membrane materials manufactured
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electrostatic spinning for oil/water separation have become one of the emerging technologies to treat oil/water emulsions. Here, we give a comprehensive review of current progress on electrospinning nanofibers for oil/water separation to promote the field's advancement. Typical examples of hydrophilic-oleophobic, hydrophobic-oleophilic, and special wettability nanofiber membranes are systematically summarized. The effects of material selection, fiber production processes, and subsequent modifications on the membrane performance are compared and discussed. Potential shortcomings of various types of separation membranes and the potential solutions are provided. The review concludes with a summary and outlook on future directions and innovations in electrospinning nanofibers and membranes for oil/water separation.
This paper gives a current summary of research advances in the field of electrospun nanofibers and nanofiber membranes for oil/water separation. And a discussion about the future field development is given.
In the past few decades, polymer solar cells (PSCs) have been intensively investigated in academic fields. The study of non-fullerene polymer acceptors has become a hot research focus due to their ...excellent opto-electronic properties such as wide light-absorbing ability, appropriate molecular energy levels, and easy chemical modifications. The much higher power conversion efficiencies (PCEs) of non-fullerene PSCs relative to fullerene PSCs revealed the significant potential of non-fullerene acceptors in PSCs. This review systematically summarizes the recent advancements of efficient polymer acceptors, including perylene diimide-based, naphthalene diimide-based, diketopyrrolopyrrole-based, double B←N bridged bipyridyl-based, and other polymer acceptors. Their structure-property relationships were thoroughly analyzed and summarized, which may provide new guidance for the rational structural design of high-performance photovoltaic materials.
Recent advances in polymer acceptors that focus on structure-property relationships, which may provide guidance for photovoltaic materials, were systematically summarized.
In recent years, rare earth complexes have become famous for their unique luminescence characteristics, such as clear emission bands, long lifetimes, and high luminous quantum efficiency. Since ...lanthanide ions have relatively small absorption areas in the ultraviolet region, they absorb light weakly. However, the excitation can be improved via coordination with organic ligands and subsequent energy transfer from the ligand triplet state to a coordinated metal ion. Electrospinning is a processing method that can readily combine rare earth complexes with matrix materials, to obtain fiber membranes with high fluorescence efficiency and stable mechanical properties. Here, we report the application of fluorescent nanofibers to color-tunable materials and oxygen sensing materials by discussing the electrospinning techniques used to produce electrospun nanofibers containing lanthanide complexes. We then focus on the mechanism of luminescence of fluorescent nanofibers, discussing polymer-based membranes and ceramic-based membranes based on the main constituent materials of the fiber membranes.
CH/PEO-SiO2@Eu3+ fiber is prepared by electrospinning. Due to the fluorescence of Eu3+ complex, the film appears red under the excitation of UV-light. When the Cu2+ solution is dropped to the film, ...the color of the film will no longer appear red, and the fluorescence of the composite chitosan nanofibers can be quickly and sensitively quenched.
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•CH/PEO-SiO2@Eu3+ nanofiber is prepared by electrospinning.•Due to the fluorescence of Eu3+ complex, the film appears red under the excitation of UV-light.•The fluorescence of the CH/PEO-SiO2@Eu3+ film can be quenched after Cu2+ solution is dropped on it.
Trace amounts of heavy metal ions in the human body are essential for maintaining health. However, heavy metal ion excess or deficiency causes toxicity or disease. This study examines the sensitivity of luminescent europium complexes for the detection of Cu2+. Here, Eu3+ is complexed with1,10-phenanthroline (phen) and 4,4′,4-trimethyltriphenylamine (TTA) to form luminescent Eu3+(TTA)3phen complexes, encapsulated in silica (SiO2) nanoparticles. The silica nanoparticles are then formed into a composite with a blend of chitosan and polyethylene oxide (PEO), to make electrospun nanofibers. The combination of Eu3+ complexes with SiO2 nanoparticles doped in chitosan enhances the fluorescence performance. Photophysical measurements show that when the Cu2+ concentration is 100 μmol/L, the fluorescence of the composite chitosan nanofibers can be quickly and sensitively quenched, and that concentrations as low as 10 μmol/L Cu2+ can be detected. Furthermore, the use of chitosan and PEO to prepare the material makes these new fluorescence-based copper sensing materials suitable for Cu2+ detection in biological systems.
Preparation of the graphene-containing fibers is an important step in the fabrication of advanced materials. However, using conventional techniques, e.g., wet or dry spinning, requires sophisticated ...recipes for fabricating the graphene oxide (GO) fibers because the GO dispersion has a low viscosity and it cannot be directly used for spinning. In this work, a simple and reliable procedure, injection spinning (IS), for a direct spinning of GO is reported. According to IS, the thin flow which is squeezed-out from a nozzle forms a flat fiber and provides the spinning drawing force to break the weak spinning thin flow of the GO water–ethanol suspension. The GO flat fiber is finally obtained by drying at a low temperature of 50 °C. The GO flat fiber is twisted and reduced by HI resulting in a production of the reduced GO (rGO) yarn. After passing the relevant characterization test, we show that varying the spinning speed changes the morphology of the rGO yarns on microscale without the appearance of appreciable changes on the nanoscale. The rGO yarns are characterized by high values of Young’s modulus about 1.5 GPa. An application is demonstrated using IS for flexible and wearable electronics.
In this work, a novel functionalized graphene oxide nucleating agent (GITP) was successfully synthesized using a silane coupling agent (IPTES), and polymer block (ITP) to efficiently improve the ...crystallization and mechanical performance of PET. To comprehensively investigate the effect of functionalized GO on PET properties, PET/GITP nanocomposites were prepared by introducing GITP into the PET matrix using the melt blending method. The results indicate that PET/GITP exhibits better thermal stability and crystallization properties compared with pure PET, increasing the melting temperature from 244.1 °C to 257.1 °C as well as reducing its crystallization half-time from 595 s to 201 s. Moreover, the crystallization temperature of PET/GITP nanocomposites was increased from 185.1 °C to 207.5 °C and the tensile strength was increased from 50.69 MPa to 66.8 MPa. This study provides an effective strategy for functionalized GO as a nucleating agent with which to improve the crystalline and mechanical properties of PET polyester.
Luminescent materials are of worldwide interest because of their unique optical properties. Silica, which is transparent to light, is an ideal matrix for luminescent materials. Luminescent silica ...nanoparticles (LSNs) have broad applications because of their enhanced chemical and thermal stability. Silica spheres of various sizes could be synthesized by different methods to satisfy specific requirements. Diverse luminescent dyes have potential for different applications. Subject to many factors such as quenchers, their performance was not quite satisfying. This review thus discusses the development of LSNs including their classification, synthesis, and application. It is the highlight that how silica improves the properties of luminescent dye and what role silica plays in the system. Further, their applications in biology, display, and sensors are also described.
The fluorescent and quantum yield (QY) of graphene quantum dots has been improved in recent years by doped atoms, which have good application prospects in fluorescence sensors and biological imaging. ...Here, a one-step hydrothermal synthesis method was used to synthesize manganese ions bonded with boron and nitrogen-doped graphene quantum dots (Mn-BN-GQDs). Compared with the boron and nitrogen co-doping graphene quantum dots (BN-GQDs),the fluorescence properties and quantum yield of Mn-BN-GQDs are significantly improved. Meanwhile, Mn-BN-GQDs exhibit low toxicity and good fluorescence imaging in living cells and has high selectivity to Fe3+ ions. Therefore, this experiment design Mn-BN-GQDs as a fluorescence sensor to detect Fe3+ ions, providing strong evidence for the advanced high sensitivity, selectivity and wide detection range of the Mn-BN-GQDs as a fluorescence sensor. These results indicate a dual linear relationship with good linear relationships in the 10–100 μM and 100–800 μM ranges, and limit of detection are 0.78 μM and 9.08 μM, respectively. Cellular imaging results demonstrate that Mn-BN-GQDs can be used as fluorescence sensors in biological imaging. Mn-BN-GQDs can be used for fluorescence sensing in biological imaging in combination with low toxicity, QY and quantum dot lifetime.
The Che-Guai region is located in the most strongly deformed area of the northwestern Junggar Basin (northwest China) and its deformation history is key to understanding the tectonic evolution of ...West Junggar and its associated hydrocarbon accumulation. However, the presence of complex multiphase structures makes it difficult to unravel the deformation history. In this study, we present comprehensive seismic and well log data, combined with geological observations from sedimentary and volcanic rocks, to reveal the structural deformation of the northwestern Junggar Basin. Based on our results, four zones of concentrated deformation are identified: (1) the Ke-Bai Fault Zone, (2) the Hongshanzui transition zone, (3) the Zhongguai uplifted zone, and (4) the Hong-Che Fault Zone. Based on the interpretation of seismic profiles, we suggest that Paleozoic strata were affected mainly by thrust faults, whereas Triassic and Jurassic strata of the Zhongguai uplifted zone were affected by strike-slip faults. Deformation in Cretaceous and Cenozoic strata is associated mainly with normal faults. Based on our results, the following tectonic history is proposed. The first stage involved initial basin formation during the Permian under the influence of northwestward subduction of the Junggar Ocean crust. The second stage, during the Triassic and Jurassic, involved transpressional deformation related to movement along the Darbute Fault. The third stage, during the Cretaceous and Cenozoic, involved moderate extensional deformation triggered by collision between the Indian and Eurasian plates. In the context of this tectonic history, hydrocarbon accumulation is proposed to be linked to fault terraces of the Hong-Che and Ke-Bai Fault Zones and the uplift of the Zhongguai Uplift.
Cyanate ester resin (CER) is an excellent thermal stable polymer. However, its mechanical properties are not appropriate for its application, with brittle weakness, and it has poor functional ...properties, such as luminescence. This work innovatively combines the luminescence property and the improved mechanical properties with the inherent thermal property of cyanate ester. A novel nanocomposite, CER/uMWCNTs/Eu, with multi-functional properties, has been prepared. The results show that with the addition of 0.1 wt.% of uMWCNTs to the resin, the flexural strength and tensile strength increased 59.3% and 49.3%, respectively. As the curing process of the CER progresses, the injected luminescence signal becomes luminescence behind the visible (FBV). The luminescence intensity of CER/uMWCNTs/Eu was much stronger than that of CER/MWCNTs/Eu, and the luminescence lifetime of CER/MWCNTs/Eu and CER/uMWCNTs/Eu was 8.61 μs and 186.39 μs, respectively. FBV exhibited great potential in the embedment of photon quantum information. Therefore, it can be predicted that CER/uMWCNTs/Eu composites will not only have a wide range of applications in sensing, detection, and other aspects, but will also exhibit great potential in the embedding of photon quantum information.
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