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1.
Polymers (Basel) ; 14(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35956697

RESUMO

Associating copolymers self-assemble during their passage through a liquid chromatography (LC) column, and the elution differs from that of common non-associating polymers. This computational study aims at elucidating the mechanism of their unique and intricate chromatographic behavior. We focused on amphiphilic diblock copolymers in selective solvents, performed the Monte Carlo (MC) simulations of their partitioning between a bulk solvent (mobile phase) and a cylindrical pore (stationary phase), and investigated the concentration dependences of the partition coefficient and of other functions describing the phase behavior. The observed abruptly changing concentration dependences of the effective partition coefficient demonstrate the significant impact of the association of copolymers with their partitioning between the two phases. The performed simulations reveal the intricate interplay of the entropy-driven and the enthalpy-driven processes, elucidate at the molecular level how the self-assembly affects the chromatographic behavior, and provide useful hints for the analysis of experimental elution curves of associating polymers.

2.
Int J Biol Macromol ; 218: 1-8, 2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35792312

RESUMO

Polycaprolactone (PCL) nanofibers have become an ideal material for bone tissue engineering due to a series of advantages. Considering the clinical treatment of bone defects, in addition to meeting the golden standard, PCL based nanofibers also need to be multifunctional to anti-inflammatory, antibacterial properties, and enhance the bone regeneration and repair. Herein, we successfully developed the multifunctional PCL/LIG/ZIF-8 composite nanofibers by loading ZIF-8 on electrospun PCL/lignin (PCL/LIG) nanofibers. The prepared composite nanofibers exhibit fairly good wettability and acceptable degradation rate, as well as excellent antioxidative stress and antibacterial properties originating from the incorporated LIG and loaded ZIF-8. Moreover, owing to the synergistic effect of LIG and ZIF-8, the composite nanofibers present excellent osteogenic differentiation, which can be verified in biomineralization experiments and real-time quantitative polymerase chain reaction. These results indicate that the PCL/LIG/ZIF-8 composite nanofibers, as potential healthcare candidate, have a promising applied in the treatment of bone defects.

3.
ACS Nano ; 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35816171

RESUMO

Colloidal quantum wells (CQWs) have emerged as a promising family of two-dimensional (2D) optoelectronic materials with outstanding properties, including ultranarrow luminescence emission, nearly unity quantum yield, and large extinction coefficient. However, the performance of CQWs-based light-emitting diodes (CQW-LEDs) is far from satisfactory, particularly for deep red emissions (≥660 nm). Herein, high efficiency, ultra-low-efficiency roll-off, high luminance, and extremely saturated deep red CQW-LEDs are reported. A key feature for the high performance is the understanding of charge dynamics achieved by introducing an efficient electron transport layer, ZnMgO, which enables balanced charge injection, reduced nonradiative channels, and smooth films. The CQW-LEDs based on (CdSe/CdS)@(CdS/CdZnS) ((core/crown)@(colloidal atomic layer deposition shell/hot injection shell)) show an external quantum efficiency of 9.89%, which is a record value for 2D nanocrystal LEDs with deep red emissions. The device also exhibits an ultra-low-efficiency roll-off and a high luminance of 3853 cd m-2. Additionally, an exceptional color purity with the CIE coordinates of (0.719, 0.278) is obtained, indicating that the color gamut covers 102% of the International Telecommunication Union Recommendation BT 2020 (Rec. 2020) standard in the CIE 1931 color space, which is the best for CQW-LEDs. Furthermore, an active-matrix CQW-LED pixel circuit is demonstrated. The findings imply that the understanding of charge dynamics not only enables high-performance CQW-LEDs and can be further applied to other kinds of nanocrystal LEDs but also is beneficial to the development of CQW-LEDs-based display technology and related integrated optoelectronics.

4.
Polymers (Basel) ; 14(11)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35683924

RESUMO

A π-conjugated small molecule N, N'-bis(naphthalen-1-yl)-N, N'-bis(phenyl)benzidine (NPB) was introduced into poly(9-vinylcarbazole) (PVK) as a hole transport layer (HTL) in inverted perovskite solar cells (PSCs). The NPB doping induces a better perovskite crystal growth, resulting in perovskite with a larger grain size and less defect density. Thus, the VOC, JSC, and FF of the PSC were all enhanced. Experimental results show that it can be ascribed to the reduction of surface roughness and improved hydrophilicity of the HTL. The effect of NPB on the aggregation of PVK was also discussed. This work demonstrates the great potential of PVK as the HTL of PSCs and provides an attractive alternative for HTL to realize high-efficiency PSCs.

5.
Macromol Rapid Commun ; : e2200347, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35686689

RESUMO

Yarn supercapacitors have attracted significant attention for wearable energy storage due to their ability to be directly integrated with garments. Conducting polymer polypyrrole (PPy) based yarn supercapacitors show limited cycling stability because of the huge volume changes during the charge-discharge processes. In addition, laundering may cause damage to such yarn supercapacitors. Here, the fabrication of PPy-based re-stickable yarn supercapacitors is reported with good cycling stability by employing vapor phase polymerization (VPP) and water-soluble polyethylene oxide (PEO) film as the adhesive layer. VPP duration and cycle are controlled to achieve multi-layered PPy electrodes. The assembled yarn supercapacitors show a good cycling stability with capacitance retention of 79.1% after 5000 charge-discharge cycles. The energy stored in the yarn supercapacitor is sufficient to power a photodetector. After gluing the yarn supercapacitors onto a PEO film, the devices can be stunk on and peeled off the garment to avoid the mechanical stresses during the washing process. Three yarn supercapacitors connected in parallel on PEO film show negative changes in electrochemical performance after 5 sticking-peeling cycles. This work provides a facile way to fabricate PPy-based re-stickable energy storage devices with high cycling stability for smart garments.

6.
Opt Lett ; 47(12): 3047-3050, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35709046

RESUMO

Deep-red CsPbI3 perovskite quantum dots (PeQDs) are essential for high-efficiency perovskite light-emitting diodes (PeLEDs) because of their high color purity and high photoluminescence quantum yield (PLQY). The synergetic strategy of indium (In) doping and chlorine (Cl) surface passivation not only partially replaced Pb2+ ions with the smaller ionic In3+ but also filled I- vacancies by Cl- on the surface, maintaining the humidity stability for more than 24 days and yielding excellent PLQY. Benefiting from this synergetic strategy, deep-red (approximately at 683 nm) CsPbI3 PeLEDs showed a maximum luminance and external quantum efficiency (EQE) of 311 cd m-2 and 8.32%, respectively.

7.
Chemosphere ; 299: 134440, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35364085

RESUMO

The transformation of plastic waste into valuable fuel products via catalytic pyrolysis is a promising and eco-friendly strategy. Herein, a series of Co/Ni pillared montmorillonites were developed as low-cost and effective catalysts for the pyrolysis of post-consumer film waste, which is one of the representative plastic wastes in nature. The best-performing catalyst produced 80.2% of liquid product, with a high selectivity of 43.5% of hydrocarbons at C10-C13 range, and 42.0 vol% of H2 which is nearly increased by 40-fold as compared to that in non-catalytic run. The improved results were ascribed to the pillared structure, the oxidation state of Co/Ni, and the distribution of acid sites. Particularly, the Lewis acidity (which governs the cyclization and alkanisation) coupled with high surface area and uniform dispersion of transition metallic sites, were found to promote the selectivity of condensable product. The pyrolytic mechanism towards H2 production was explored by theoretical calculations. The lattice oxygen bonded to both Ni and Co in an octahedral environment was found to promote the adsorption of the fragment of polymer in dehydrogenation. Additionally, the solid residues are potentially applied for the production of valuable carbonaceous materials since they displayed high heating value. This work is expected to provide a direction for the development of pyrolysis technology for fuel production with sustainability and economic viability.

8.
Materials (Basel) ; 15(8)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35454447

RESUMO

Recent studies have shown that the introduction of silicon can effectively improve the dielectric properties of polyimide (PI), and the introduction of a silicon-oxygen bond can increase the flexibility of the PI molecular structure, which is conducive to reducing the moisture absorption rate of PI materials. In this experiment, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyl disiloxane (DSX) was mixed with 4,4'-diaminodiphenyl ether (ODA) in different proportions. A series of PI films containing silicon was obtained by random polymerization with pyromellitic dianhydride (PMDA), 3,3',4,4'-diphenylketotetrahedral anhydride (BTDA) and biphenyl dianhydride (BPDA), and then tetrad copolymerization with three kinds of dianhydrides. At the same time, the PI structures were put into calculation software to obtain the simulated polarization results, and then the films were characterized by various properties. The results showed that the characterization results were consistent with that of simulation, and the best overall PI formula was when the ratio of diamines was 1:9 and mixed with PMDA. The performance data were as follows: the vitrification temperature was about 320 °C, T5 was 551 °C, water absorption was 1.56%, dielectric constant (Dk) was 2.35, dielectric loss (Df) was 0.007, tensile strength was 70 MPa and elongation at break was 10.2%.

9.
Polymers (Basel) ; 14(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35160390

RESUMO

Nonradiative recombination losses caused by defects in the perovskite layer seriously affects the efficiency and stability of perovskite solar cells (PSCs). Hence, defect passivation is an effective way to improve the performance of PSCs. In this work, trichloromelamine (TCM) was used as a defects passivator by adding it into the perovskite precursor solution. The experimental results show that the power conversion efficiency (PCE) of PSC increased from 18.87 to 20.15% after the addition of TCM. What's more, the environmental stability of PSCs was also improved. The working mechanism of TCM was thoroughly investigated, which can be ascribed to the interaction between the -NH- group and uncoordinated lead ions in the perovskite. This work provides a promising strategy for achieving highly efficient and stable PSCs.

10.
Front Chem ; 10: 835455, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35198540

RESUMO

How to construct a functional unit for heat storage by using biomass materials is significant for the exploration of phase change materials (PCMs). In this work, we try to design and construct a functional unit for heat storage by employing a vacuum impregnation method to prepare sugarcane-based shape stabilized phase change materials (SSPCMs) for improving the thermal conductivity of phase change materials (PCMs) and preventing the liquid state leakage of PCMs. The morphologies of the prepared materials are characterized by Scanning electron microscope (SEM) as containing a unique channel structure which is viewed as the key factor for heat storage. X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA) were used to characterize the prepared materials. The results indicated that no chemical reaction occurred between PEG and sugarcane-based biomass during the preparation process and SSPCMs showed great thermal stability. Their thermal properties are measured by using the differential scanning calorimetry (DSC) characterization and show a high melting enthalpy of 140.04 J/g and 94.84% of the relative enthalpy efficiency, illustrating the excellent shape stabilized phase change behavior. Moreover, the highest thermal conductivity of SSPCMs is up to 0.297 W/(mK), which is 28.02% higher than that of the pristine PEG. The excellent capability for thermal energy storage is attributed to the directional thermal conduction skeletons and perfect open channels and the unique anisotropic three-dimensional structure of the SSPCMs. Hence, the unique structure with PEG is testified as the functional unit for heat storage. Comprehensively considering the excellent properties of sugarcane-based materials-providing cheap raw materials via green preparation-it is conceived that sugarcane-based materials could be applied in many energy-related devices with reasonable function unit design.

11.
J Colloid Interface Sci ; 608(Pt 1): 830-839, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34689112

RESUMO

HYPOTHESIS: The intricate entropy-enthalpy interplay of dendrimers confined in pores affects their conformation and retention in the porous stationary phase. This work aims at providing important insights into its impacts on partitioning and chromatographic separation in both size-exclusion chromatography (SEC) and interaction chromatography (IC) regimes. SIMULATIONS: Using Monte Carlo (MC) simulations, we investigated the bulk-pore phase equilibria and the conformational behavior of flexible dendrimers differing in generation, in spacer length and in fraction of modified terminal groups interacting differently with pore walls than the majority building units. FINDINGS: With increasing interaction strength, a distinct transition from a roughly spherical shape caused by simultaneous interactions with two walls to an ellipsoidal (or even disklike) conformation tenaciously adhering to only one wall was observed for moderately confined dendrimers. The strongly deformed dendrimers subjected to severe confinement gain high energy and the samples differing in the degree of modification become chromatographically discernable thanks to large energy differences. Consequently, our results suggest that the column fillings with fairly narrow pores which are ineffective in SEC, are highly efficient separation media for dendrimer studies by IC above the critical adsorption point (CAP). Overall, our simulations reveal useful information for advancing and optimizing experimental liquid chromatography studies of dendrimers.


Assuntos
Dendrímeros , Conformação Molecular , Método de Monte Carlo , Porosidade , Termodinâmica
12.
ACS Appl Mater Interfaces ; 13(43): 50836-50850, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34689546

RESUMO

Polyetheretherketone (PEEK) is a biocompatible polymer, but its clinical application is largely limited due to its inert surface. To solve this problem, a multifunctional PEEK implant is urgently fabricated. In this work, a dual-metal-organic framework (Zn-Mg-MOF74) coating is bonded to PEEK using a mussel-inspired polydopamine interlayer to prepare the coating, and then, dexamethasone (DEX) is loaded on the coating surface. The PEEK surface with the multifunctional coating provides superior hydrophilicity and favorable stability and forms an alkaline microenvironment when Mg2+, Zn2+, 2,5-dihydroxyterephthalic acid, and DEX are released due to the coating degradation. In vitro results showed that the multifunctional coating has strong antibacterial ability against both Escherichia coli and Staphylococcus aureus; it also improves human umbilical vein endothelial cell angiogenic ability and enhances rat bone marrow mesenchymal stem cell osteogenic differentiation activity. Furthermore, the in vivo rat subcutaneous infection model, chicken chorioallantoic membrane model, and rat femoral drilling model verify that the PEEK implant coated with the multifunctional coating has strong antibacterial and angiogenic ability and promotes the formation of new bone around the implant with a stronger bone-implant interface. Our findings indicate that DEX loaded on the Zn-Mg-MOF74 coating-modified PEEK implant with bacteriostasis, angiogenesis, and osteogenesis properties has great clinical application potential as bone graft materials.


Assuntos
Antibacterianos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Estruturas Metalorgânicas/farmacologia , Neovascularização Patológica/tratamento farmacológico , Adsorção , Animais , Antibacterianos/síntese química , Antibacterianos/química , Benzofenonas/química , Benzofenonas/farmacologia , Dexametasona/química , Dexametasona/farmacologia , Escherichia coli/efeitos dos fármacos , Magnésio/química , Magnésio/farmacologia , Masculino , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Neovascularização Patológica/microbiologia , Polímeros/química , Polímeros/farmacologia , Ratos , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos , Zinco/química , Zinco/farmacologia
13.
Macromol Biosci ; 21(7): e2100047, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33893711

RESUMO

Tissue engineering scaffolds provide an encouraging alternative for nerve injuries due to their biological support for nerve cell growth, which can be used for neuronal repair. Nerve cells have been reported to be mostly cultured on 2D scaffolds that cannot mimic the native extracellular matrix. Herein, highly ordered 3D scaffolds are fabricated for nerve cell culture by melt electrospinning writing, the microstructures and geometries of the scaffolds could be well modulated. An effective strategy for scaffold surface modification to promote nerve cell growth is proposed. The effects of scaffolds with different surface modifications, viz., plasma treatment, single poly-D-lysine (PDL) coating after plasma treatment, single laminin (LM) coating after plasma treatment, double PDL and LM coatings after plasma treatment, on PC12 cell growth are evaluated. Experiments show the scaffold modified with double PDL and LM coatings after plasma treatment facilitated the growth of PC12 cells most effectively, indicating the synergistic effect of PDL and LM on the growth of nerve cells. This is the first systematic and quantitative study of the effects of different scaffold surface modifications on nerve cell growth. The above results provide a versatile culture platform for growing nerve cells, and for recovery from peripheral nerve injury.


Assuntos
Tecido Nervoso , Engenharia Tecidual , Animais , Proliferação de Células , Neurônios/metabolismo , Ratos , Engenharia Tecidual/métodos , Tecidos Suporte/química
14.
Nanoscale Res Lett ; 16(1): 4, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33404823

RESUMO

Conductive and degradable nanofibrous scaffolds have great potential in promoting cell growth, proliferation, and differentiation under an external electric field. Although the issue of inferior electrical conductivity in body fluids still exists, polyaniline (PANI)-based degradable nanofibers can promote cell adhesion, growth, and proliferation. To investigate whether the effect is caused by the PANI morphology, we selected three inorganic acids as dopants in the process of PANI in situ oxidative polymerization: hydrochloric acid, sulfuric acid, and perchloric acid. The obtained polyaniline/polylactic acid (PANI/PLA) composite nanofibers were characterized via SEM, FTIR, and XPS analysis, and we confirmed that the PLA nanofibers were successfully coated by PANI without any change to the porous structure of the PLA nanofibers. The in vitro mechanical properties and degradability indicated that the oxidation of acid dopants should be considered and that it was likely to have a higher oxidation degradation effect on PLA nanofibers. The contact angle test demonstrated that PANI/PLA composite nanofibers with different surface morphologies have good wettability, implying that they meet the requirements of bone tissue engineering scaffolds. The surface roughness and cell viability demonstrated that different PANI morphologies on the surface can promote cell proliferation. The higher the surface roughness of the PANI, the better the biocompatibility. Consequently, the regulated surface morphology of PANI/PLA composite nanofibers via different acids doping has positive effect on biocompatibility in tissue engineering.

15.
Polymers (Basel) ; 12(10)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32992709

RESUMO

In this work, a few-layer MXene is prepared and sprinkled on a commercial polypropylene (PP) separator by a facile spraying method to enhance the electrochemistry of the Ni-rich LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode. Scanning electron microscope (SEM) and X-ray diffraction (XRD) are used to characterize the morphology and structure of MXene. Fourier transform infrared spectroscopy (FT-IR) and a contact angle tester are used to measure the bond structure and surface wettability PP and MXene/PP separator. The effect of the MXene/PP separator on the electrochemical performance of ternary NCM811 material is tested by an electrochemical workstation. The results show that the two-dimensional MXene material could improve the wettability of the separator to the electrolyte and greatly enhance the electrochemical properties of the NCM811 cathode. During 0.5 C current density cycling, the Li/NCM811 cell with MXene/PP separator remains at 166.2 mAh/g after the 100 cycles with ~90.7% retention. The Rct of MXene/PP cell is measured to be ~28.0 Ω. Combining all analyses results related to MXene/PP separator, the strategy by spraying the MXene on commercial PP is considered as a simple, convenient, and effective way to improve the electrochemical performance of the Ni-rich NCM811 cathode and it is expected to achieve large-scale in high-performance lithium-ion batteries in the near future.

16.
ACS Appl Mater Interfaces ; 12(37): 41852-41860, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32811138

RESUMO

Recent advances in non-fullerene acceptors (NFAs) have resulted in significant improvement in the power conversion efficiencies (PCEs) of organic solar cells (OSCs). In our efforts to boost open-circuit voltage (VOC) for OSCs, the molecular design employing thiobarbituric acid (TBTA) end groups and an indacenodithieno[3,2-b]thiophene (IDTT) core gives rise to NFAs with significantly raised lowest unoccupied molecular orbital (LUMO) energy level, which, when paired with PCE10, can achieve VOC's over 1.0 V and decent PCEs that outperform the equivalent devices based on the benchmark ITIC acceptor. While the use of a TBTA end group is effective in tuning energy levels, very little is known about how the alkyl substitution on the TBTA group impacts the solar cell performance. To this end, TBTA end groups are alkylated with linear, branched, and aromatic sidechains to understand the influence on thin-film morphology and related device performances. Our study has confirmed the dependence of solar cell performance on the end-group substituents. More importantly, we reveal the presence of an ideal window of crystallinity associated with the medium-length hydrocarbon chains such as ethyl and benzyl. Deviation to the shorter methyl group makes the acceptor too crystalline to mix with the polymer donor and form proper domains, whereas longer and branched alkyl chains are too sterically bulky and hinder charge transport due to nonideal packing. Such findings underline the comprehensive nature of thin-film morphology and the subtle end-group effects for the design of non-fullerene acceptors.

17.
ACS Appl Mater Interfaces ; 12(14): 16387-16393, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32180392

RESUMO

Ternary organic solar cells (OSCs) provide a convenient and effective means to further improve the power conversion efficiency (PCE) of binary ones via composition control. However, the role of the third component remains to be explored in specific binary systems. Herein, we report ternary blend solar cells by adding the narrow-band-gap donor PCE10 as the mediator into the PBDB-T:IDTT-T binary blend system. The extended absorption, efficient fluorescence resonance energy transfer, enhanced charge dissociation, and induced tighter molecular packing of the ternary blend films enhance the photovoltaic properties of devices and deliver a champion PCE of 10.73% with an impressively high open-circuit voltage (VOC) of 1.03 V. Good miscibility and similar molecular packing behavior of the components guarantee the desired morphology in the ternary blend films, leading to solar cell devices with over 10% PCEs at a range of compositions. Our results suggest that ternary systems with properly aligned energy levels and overlapping absorption among the components hold great promises to further enhance the performance of corresponding binary ones.

18.
J Hazard Mater ; 384: 121367, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629589

RESUMO

Generally, the efficiency of water purification can be greatly increased by a high-flux membrane separation technology. One major challenge in the application of this technology is to achieve high removal efficacy of target pollutants with elevated water flux. Here we report a novel self-assembled composite by depositing two-dimensional MXene nanosheets on a commercialized mixed cellulose ester filter (as designated as MCM). Morphology study reveals that MCM exhibits an ultrathin flaked structure with uniform nanochannels which is stapled on a porous support. The tailored membrane has been successfully applied in the methylene blue solution treatment and 100% ± 0.1% removal rate is achieved while the feed concentration of dye solution is up to 90 mg·L-1. Concurrently, stable and comparatively elevated water flux was achieved, i.e., 28.94 ± 0.74 L·m-2·h-1, which is 1.88-fold of that of the commercialized UTC60 membrane. Further investigations on the separation mechanism are performed to get more insights into separation performance exhibited by MCM. It is found that the size-selective sieving, electrostatic repulsion of MXene and the high porosity of substrate play the synergistic effect on the fast and efficient dye removal behavior. Taken together, the composite membrane fabricated in present work provides an alternatively high-efficiency approach for dye treatment, and unflagging efforts will be further invested on the development and large-scale application of MXene-based membrane.

19.
Sci Rep ; 9(1): 18232, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796835

RESUMO

Enhancing the injection of electron is an effective strategy to improve the performance of polymer light-emitting diodes (PLEDs). In this work, we reported a 286% improvement in current efficiency (CE) of PLEDs by using double-layered alkali halide electron injection layer (EIL) NaCl/LiF instead of LiF. A significant enhancement of electron injection was observed after inserting the NaCl layer. To understand the mechanism of such improvement, the devices with KBr/LiF and CsF/LiF as EILs were also investigated. Experimental results show that metal cation migrated under the effect of built-in electric field (Vbi), which plays the main role on the improvement of electron injection in PLEDs.

20.
Polymers (Basel) ; 11(12)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783562

RESUMO

Tremendous efforts have been made toward the development of lithium-sulfur (Li-S) batteries as one of the most reasonable solutions to the rapidly increasing demand for portable electronic devices and electric vehicles, owing to their high cost-efficiency and theoretical energy density. However, the shuttle effect caused by soluble polysulfides is generally considered to be an insurmountable challenge, which can significantly reduce the battery lifecycle and sulfur utilization. Here, we report a lignin nanoparticle-coated Celgard (LC) separator to alleviate this problem. The LC separator enables abundant electron-donating groups and is expected to induce chemical binding of polysulfides to hinder the shuttle effect. When a sulfur-containing commercially available acetylene black (approximately 73.8 wt% sulfur content) was used as the cathode without modification, the Li-S battery with the LC separator presented much enhanced cycling stability over that with the Celgard separator for over 500 cycles at a current density of 1 C. The strategy demonstrated in this study is expected to provide more possibilities for the utilization of low-cost biomass-derived nanomaterials as separators for high-performance Li-S batteries.

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