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1.
RSC Adv ; 14(7): 4607-4613, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38318614

RESUMO

Enhancing the oxygen reduction reaction (ORR) activity and stability of the fuel cell cathode electrocatalysts and reducing their costs are critical. In response to this need, Fe, B, and N co-doped hollow mesoporous carbon materials were prepared by a simple chemical doping one-step pyrolysis method using ZIF-8 as a precursor. The results showed that the optimized catalyst displayed a higher limiting current density (6.154 mA cm-2) and half-wave potential (0.859 V), which showed significant enhancement compared with the Pt/C catalyst (5.487 mA cm-2 and 0.853 V). Moreover, the optimized catalyst had outstanding long-term stability with a current density retention higher than 91% after 36 000 s of stability testing. This work provides a facile strategy for the design of outstanding ORR performance of non-precious metal oxygen reduction catalysts.

2.
J Colloid Interface Sci ; 650(Pt B): 1536-1549, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37487284

RESUMO

Photocatalysis shows huge potential in environmental purification, but suffers from fast photocharge recombination and finite photoabsorption. Piezoelectric polarization is perceived as a promising approach to drive charge separation, but it always relies on the energy-guzzling ultrasonic vibration. Herein, a piezo-photocatalytic system integrating dual electric fields constructed by weak force-driven piezoelectric polarization and Z-scheme junction is developed in 0D/2D α-Fe2O3/Bi2WO6. The introduction of low-frequency water flow-induced piezoelectric polarization field accelerates the migration of bulk photoexcited carriers of polar Bi2WO6, and forming Z-scheme junction with intimate interface guarantees the spatial separation of interfacial charges and strong visible light response. Benefiting from these merits, water flow-triggered α-Fe2O3/Bi2WO6 delivers a superb tetracycline hydrochloride photodegradation efficiency of 82% within 20 min, which outperforms related piezo-photocatalysts in previous reports, even those driven by high-frequency ultrasound. KPFM and DFT calculations provide forceful evidence for the Z-scheme transfer pathway between α-Fe2O3 and Bi2WO6. Additionally, the synergetic effect of constructing the Z-scheme junction and introducing piezoelectric polarization is well confirmed by PFM, COMSOL simulation, ESR and photoelectrochemical characterization. This work offers a novel strategy to design the piezo-photocatalytic system and maybe realize the in-situ treatment of sewage taking full advantage of hydrodynamic characteristics.

3.
Int J Nanomedicine ; 18: 2891-2910, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283712

RESUMO

Introduction: Hepatocellular cancer stem cells (CSCs) play crucial roles in hepatocellular cancer initiation, development, relapse, and metastasis. Therefore, eradication of this cell population is a primary objective in hepatocellular cancer therapy. We prepared a nanodrug delivery system with activated carbon nanoparticles (ACNP) as carriers and metformin (MET) as drug (ACNP-MET), which was able to selectively eliminate hepatocellular CSCs and thereby increase the effects of MET on hepatocellular cancers. Methods: ACNP were prepared by ball milling and deposition in distilled water. Suspension of ACNP and MET was mixed and the best ratio of ACNP and MET was determined based on the isothermal adsorption formula. Hepatocellular CSCs were identified as CD133+ cells and cultured in serum-free medium. We investigated the effects of ACNP-MET on hepatocellular CSCs, including the inhibitory effects, the targeting efficiency, self-renewal capacity, and the sphere-forming capacity of hepatocellular CSCs. Next, we evaluated the therapeutic efficacy of ACNP-MET by using in vivo relapsed tumor models of hepatocellular CSCs. Results: The ACNP have a similar size, a regular spherical shape and a smooth surface. The optimal ratio for adsorption was MET: ACNP=1:4. ACNP-MET could target and inhibit the proliferation of CD133+ population and decrease mammosphere formation and renewal of CD133+ population in vitro and in vivo. Conclusion: These results not only suggest that nanodrug delivery system increased the effects of MET, but also shed light on the mechanisms of the therapeutic effects of MET and ACNP-MET on hepatocellular cancers. ACNP, as a good nano-carrier, could strengthen the effect of MET by carrying drugs to the micro-environment of hepatocellular CSCs.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Metformina , Nanopartículas , Humanos , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/patologia , Carvão Vegetal , Linhagem Celular Tumoral , Metformina/farmacologia , Células-Tronco Neoplásicas/patologia , Nanopartículas/uso terapêutico , Antígeno AC133/metabolismo , Antígeno AC133/farmacologia , Microambiente Tumoral
4.
Angew Chem Int Ed Engl ; 62(26): e202301631, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37017994

RESUMO

High energy density and intrinsic safety are the central pursuits in developing rechargeable Zinc-ion batteries (ZIBs). The capacity and stability of nickel cobalt oxide (NCO) cathode are unsatisfactory because of its semiconductor character. Herein, we propose a built-in electric field (BEF) approach by synergizing cationic vacancies and ferroelectric spontaneous polarization on cathode side to facilitate electron adsorption and suppress zinc dendrite growth on the anode side. Concretely, NCO with cationic vacancies was constructed to expand lattice spacing for enhanced zinc-ion storage. Heterojunction with BEF leads to the Heterojunction//Zn cell exhibiting a capacity of 170.3 mAh g-1 at 400 mA g-1 and delivering a competitive capacity retention of 83.3 % over 3000 cycles at 2 A g-1 . We conclude the role of spontaneous polarization in suppressing zinc dendrite growth dynamics, which is conducive to developing high-capacity and high-safety batteries via tailoring defective materials with ferroelectric polarization on the cathode.


Assuntos
Dendritos , Zinco , Cátions , Eletrodos
5.
J Colloid Interface Sci ; 635: 94-104, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36577358

RESUMO

Carbon-based zinc-ion capacitors (ZICs) have sparked intense research enthusiasm because of large power density, good rate capability and cycling stability. However, there is still a long way to go before they achieve commercial applications. Herein, oxygen-enriched lignin-derived porous carbon nanosheets (OLCKs) were prepared by one-step carbonization-activation method, and more O-containing functional groups were generated on the surface of the porous carbon by post-surface functionalization strategy. The self-doped N can change the electron distribution of carbon skeleton and decrease energy barrier of chemical absorption of Zn2+/H+. Meanwhile, the carbonyl group can significantly enhance the wettability of OLCKs. Furthermore, the diffusion-controlled reactions mainly exist at high and low potential ranges in CV curves, which demonstrates the occurred Faradaic reaction. Consequently, the assembled aqueous ZICs based on OLCKs demonstrate a capacity of 121.7 mAh/g at 0.3 A/g, energy density of 94.3 Wh kg-1 and good cyclic stability. Besides, the assembled Zn//PVA/LiCl/ZnCl2(gel)//OLCK4 ZIC can also achieve energy density of 134.4 Wh kg-1 at 0.1 A/g. This work provides a novel design strategy by incorporating abundant O and N-containing functional groups to enhance energy density.

6.
J Colloid Interface Sci ; 630(Pt A): 742-753, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36279835

RESUMO

The exploration of novel nanomaterials to resolve the issues of water pollution with the aid of photocatalytic technology has always been a research hotspot. MoS2 is acknowledged to be one of the promising photocatalysts for its interesting layered structure, suitable band gap, and good chemical stability. However, the fast recombination of photogenerated electrons and holes within the MoS2 impedes its extensive application. Here, hydrophilic polymer (polyvinyl pyrrolidone, PVP) and sulfur vacancy (Vs) are simultaneously introduced into the MoS2 nanosheets to achieve high-efficient photocatalytic hexavalent chromium Cr(VI) removal and antibacterial performance. The incorporation of PVP greatly enhances the adsorption capacity of MoS2, and creating Vs essentially strengthens the photogenerated carrier separation of MoS2. As a result, the Cr(VI) removal efficiency of MoS2-PVP with an appropriate Vs concentration is up to 99.5 % for 3 h. Meanwhile, MoS2-PVP with a relatively higher Vs concentration displays a superior Escherichia coli (E. coli) removal efficiency of 91.8 % within 30 min with the initial E. coli concentration of âˆ¼1.0 × 107 CFU/mL. This study extends photocatalysts to a higher level in designing advanced materials for environmental remediation and establishes a feasible platform for emphasizing the versatility of defect engineering in regulating catalytic activity.


Assuntos
Molibdênio , Poluentes Químicos da Água , Adsorção , Escherichia coli , Poluentes Químicos da Água/química , Cromo/química , Esterilização
7.
J Colloid Interface Sci ; 629(Pt A): 1055-1065, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36174252

RESUMO

High value-added recycling of hazardous substances emerges as one of the most promising directions in current society, which can simultaneously relieve the environmental burden and obtain useful products. Here, we propose a transformation strategy from adsorbent to photocatalyst by recycling heavy metal with natural clay mineral. Sepiolite is selected as an adsorbent for removing Cd2+ in wastewater due to its excellent adsorption properties in terms of high specific surface area and structural channels. Then, in-situ sulfidation of the adsorbed Cd2+ is carried out, transforming it into CdS/Sep photocatalyst, which exhibits efficient photocatalytic antibacterial activity for Escherichia coli with a sterilization efficiency of 98.8% within 2 h. The intense visible light absorption of CdS and the efficient separation of photogenerated carriers render the prominent antibacterial activity. The main reactive species including superoxide radicals and hydroxyl radicals produced by CdS/Sep under visible light irradiation are diffused into the solution and attack the bacteria surrounding the photocatalysts. This work not only develops new ideas for recycling heavy metals for fabrication of efficient photocatalysts, but also provides a reference for water purification based on cost-effective natural minerals.


Assuntos
Cádmio , Metais Pesados , Argila , Águas Residuárias/química , Catálise , Superóxidos , Luz , Antibacterianos/farmacologia , Antibacterianos/química , Metais Pesados/farmacologia , Escherichia coli , Substâncias Perigosas
8.
RSC Adv ; 12(52): 33981-33987, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36505686

RESUMO

Transition metal and nitrogen codoped carbon materials have emerged as one of the most promising candidates to replace noble metal-based oxygen reduction reaction (ORR) catalysts. However, the development of high-efficiency, stable and low-cost metal-nitrogen-carbon catalysts still remains a challenge. In this study, cobalt and nitrogen codoped carbon sheet catalysts were successfully prepared by a simple self-injected vapor phase growth and template method. The catalysts exhibited a multilevel pore structure with a large specific surface area and resulting physical characteristics. The catalysts have excellent onset and half-wave potentials during the ORR. Notably, the onset (E 0) and half-wave potential (E 1/2) in alkaline media for the Co-N-C-43.8 catalyst are 31 mV and 3 mV higher than those of a commercial Pt/C catalyst, respectively. Moreover, the durability of the Co-N-C-43.8 catalyst remains at a 93% current density after 10 000 s, while that of a commercial Pt/C catalyst only remains at 83%. Also, the Co-N-C-43.8 catalyst has little change in the current density after the addition of methanol. These results indicate that the Co,N-doped carbon sheet is a promising ORR catalyst.

9.
ACS Appl Mater Interfaces ; 14(32): 36668-36678, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35939330

RESUMO

A major drawback of α-MnO2-based zinc-ion batteries (ZIBs) is the poor rate performance and short cycle life. Herein, an oxygen-deficient α-MnO2 nanotube (VO-α-MnO2)-integrated graphene (G) and N, P codoped cross-linked porous carbon nanosheet (CNPK) composite (VO-α-MnO2/CNPK/G) has been prepared for advanced ZIBs. The introduction of VO in MnO2 can decrease the value of the Gibbs free energy of Zn2+ adsorption near VO (ca. -0.73 eV) to the thermal neutral value. The thermal neutral value demonstrates that the Zn2+ adsorption/desorption process on VO-α-MnO2 is more reversible than that on α-MnO2. The as-made Zn/VO-α-MnO2 battery is able to deliver a large capacity of 305.0 mAh g-1 and high energy density up to 408.5 Wh kg-1. The good energy storage properties can be attributed to VO. Additionally, the VO-α-MnO2/CNPK/G composite possesses the structure of nanotube arrays, which results from the vertical growth of α-MnO2 nanotubes on CNPK. This unique array structure helps to realize fast ion/electron transfer and stable microstructure. The electrochemical performance of VO-α-MnO2 has been comprehensively improved by compositing with G and CNPK. The VO-α-MnO2/CNPK/G can achieve capacity up to 405.2 mAh g-1, energy density of 542.2 Wh kg-1, and long cycle life (80% capacity retention after 2000 cycles).

10.
Nanoscale ; 14(5): 2004-2012, 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35072192

RESUMO

Zinc-ion hybrid capacitors (ZIHCs) are regarded as a potential candidate for large-scale energy storage devices. However, the inadequate cathode and the inferior wettability between the electrode and electrolyte hinder the construction of high-performance ZIHCs. Herein, boron (B) and sulfur (S) co-doped spongy-like hierarchically porous carbon (B2S3C) is first proposed as a cathode material for ZIHCs. Here, B doping is favorable for improving the wettability, while S doping contributes to enhancing the electrical properties. In addition, the density functional theory (DFT) results uncover that B and S atoms contribute to reducing the energy barrier between Zn2+ and the cathode, leading to boosted chemical adsorption ability of Zn2+ on the cathode. As a result, the assembled ZIHC based on B2S3C exhibits a high specific capacity of 182.6 mA h g-1 at 0.1 A g-1, an excellent capacity retention of 96.2% after 10 000 cycles and a remarkable energy density of 292.2 W h kg-1 at a power density of 62.2 W kg-1, superior to the previously reported ZIHCs. Due to the flexibility of the assembled electrodes, the solid-state ZIHC can sustain various deformations. This work paves a feasible path for the development of cost-effective and high-performance porous carbon materials.

11.
Turk J Gastroenterol ; 32(11): 923-931, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34872893

RESUMO

BACKGROUND: The research aimed to observe the effect of gene silencing on the proliferation, migration, cell cycle, apoptosis, and other biological functions of human gastric cancer cells with RNA interference inhibiting the expression of the far upstream element-binding protein 1 (FUBP1) in the gastric cancer cell line SGC7901. METHODS: The shRNA lentivirus vector of the target gene FUBP1 was constructed to transfect the gastric cancer cell line SGC7901. The qRT-PCR and western blot assays were used to detect the expression levels of FUBP1 mRNA and protein in the gastric cancer cells. The CCK-8 assay was used to detect the proliferation of gastric cancer cells. The cell scratch assay and the transwell assays were used to detect the migration of gastric cancer cells. Flow cytometry was used to detect cell cycle distribution and apoptosis. RESULTS: The shRNA lentiviral vector of FUBP1 was successfully transfected into the gastric cancer cell line SGC7901, and could effectively reduce the expression of mRNA and protein of FUBP1. The silencing of FUBP1 could inhibit the gastric cancer cell proliferation and affect the distribution of the cell cycle, resulting in S-phase arrest and cell growth inhibition. However, FUBP1 silencing has no significant effect on cell apoptosis and migration. CONCLUSIONS: The expression of FUBP1 can be inhibited specifically and effectively by RNA interference technology, which can significantly affect the biological function of the gastric cancer cell line SGC7901.


Assuntos
Proteínas de Ligação a DNA , Interferência de RNA , Proteínas de Ligação a RNA , Neoplasias Gástricas , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-34691215

RESUMO

Osthole has been isolated from the fruits of Cnidium monnieri (L.) Cusson, which has been used in Chinese traditional medicine to treat pruritic disorders for a long time. However, the antipruritic mechanism of osthole is not fully understood. In the present study, using calcium imaging, molecular docking, and animal scratching behavior, we analyzed the pharmacological effects of osthole on transient receptor potential vanilloid 1 (TRPV1). The results showed that osthole significantly induced calcium influx in a dose-dependent manner in dorsal root ganglion (DRG) neurons. Osthole-induced calcium influx was inhibited by AMG9810, an antagonist of TRPV1. Osthole and the TRPV1 agonist capsaicin-induced calcium influx were desensitized by pretreatment with osthole. Furthermore, molecular docking results showed that osthole could bind to TRPV1 with a hydrogen bond by anchoring to the amino acid residue ARG557 in the binding pocket of TRPV1. In addition, TRPV1 is a downstream ion channel for the histamine H1 and H4 receptors to transmit itch signals. Osthole attenuated scratching behavior induced by histamine, HTMT (histamine H1 receptor agonist), and VUF8430 (histamine H4 receptor agonist) in mice. These results suggest that osthole inhibition of histamine-dependent itch may be due to the activation and subsequent desensitization of TRPV1 in DRG neurons.

13.
J Mater Chem B ; 9(4): 1138-1150, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33432964

RESUMO

Gold nanomaterials are widely used in biomedical research as drug delivery systems, imaging agents and therapeutic materials owing to their unique physicochemical properties and high biocompatibility. In this study, we prepared ultra-small gold nanoparticles (AuNPs) and induced them with gadolinium ions to form a spherical self-assembly. The nanoparticles were coupled with matrix metalloproteinase-2 (MMP-2) and loaded with the photosensitive drug IR820 for photothermal/photodynamic combination therapy of liver cancer. The formed nanoprobes were metabolised in vivo via degradation under dual-mode real-time imaging because of their acid response degradation characteristics. In addition, the nanoprobe showed excellent tumour-targeting ability due to the presence of surface-modified MMP-2. In vivo treatment experiments revealed that the nanoprobes achieved enhanced photodynamic/photothermal combination therapy under laser irradiation and significantly inhibited tumour growth. Therefore, the nanoprobes have great potential for anti-tumour therapy guided by dual-mode real-time imaging of liver cancer.


Assuntos
Antineoplásicos/farmacologia , Gadolínio/farmacologia , Ouro/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas Metálicas/química , Fotoquimioterapia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Gadolínio/química , Ouro/química , Humanos , Íons/química , Íons/farmacologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Tamanho da Partícula , Propriedades de Superfície , Células Tumorais Cultivadas
14.
Int J Nanomedicine ; 15: 7013-7034, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061365

RESUMO

PURPOSE: Gastric cancer stem cells (CSCs) are important for the initiation, growth, recurrence, and metastasis of gastric cancer, due to their chemo-resistance and indefinite proliferation. Herein, to eliminate gastric CSCs, we developed novel CSC-targeting glioma-associated oncogene homolog 1 (Gli1) small interfering RNA (siRNA) nanoparticles that are specifically guided by a di-stearoyl-phosphatidyl-ethanolamine- hyaluronic-acid (DSPE-HA) single-point conjugate, as an intrinsic ligand of the CD44 receptor. We refer to these as targeting Gli1 siRNA nanoparticles. METHODS: We used the reductive amination reaction method for attaching amine groups of DSPE to aldehydic group of hyaluronic acid (HA) at the reducing end, to synthesize the DSPE-HA single-point conjugate. Next, targeting Gli1 siRNA nanoparticles were prepared using the layer-by-layer assembly method. We characterized the stem cellular features of targeting Gli1 siRNA nanoparticles, including their targeting efficiency, self-renewal capacity, the migration and invasion capacity of gastric CSCs, and the penetration ability of 3D tumor spheroids. Next, we evaluated the therapeutic efficacy of the targeting Gli1 siRNA nanoparticles by using in vivo relapsed tumor models of gastric CSCs. RESULTS: Compared with the multipoint conjugates, DSPE-HA single-point conjugates on the surface of nanoparticles showed significantly higher binding affinities with CD44. The targeting Gli1 siRNA nanoparticles significantly decreased Gli1 protein expression, inhibited CSC tumor spheroid and colony formation, and suppressed cell migration and invasion. Furthermore, in vivo imaging demonstrated that targeting Gli1 siRNA nanoparticles accumulated in tumor tissues, showing significant antitumor recurrence efficacy in vivo. CONCLUSION: In summary, our targeting Gli1 siRNA nanoparticles significantly inhibited CSC malignancy features by specifically blocking Hedgehog (Hh) signaling both in vitro and in vivo, suggesting that this novel siRNA delivery system that specifically eliminates gastric CSCs provides a promising targeted therapeutic strategy for gastric cancer treatment.


Assuntos
Receptores de Hialuronatos/genética , Nanopartículas/química , Células-Tronco Neoplásicas/efeitos dos fármacos , RNA Interferente Pequeno/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Proteína GLI1 em Dedos de Zinco/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Terapia Genética/métodos , Proteínas Hedgehog/metabolismo , Humanos , Ácido Hialurônico/química , Masculino , Camundongos Endogâmicos BALB C , Terapia de Alvo Molecular/métodos , Nanoconjugados/administração & dosagem , Nanoconjugados/química , Nanopartículas/administração & dosagem , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fosfatidiletanolaminas/química , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Artigo em Inglês | MEDLINE | ID: mdl-32454868

RESUMO

Atopic dermatitis (AD) is a common inflammatory skin disease characterized by intense pruritus and skin lesions. The exact cause of AD is not yet known and the available therapeutic strategies for AD are limited. Fructus cnidii is commonly used in traditional Chinese medicine as an herb for treating chronic itch. However, the mechanism underlying the antipruritic effects of Fructus cnidii is not well understood. In the present study, we investigated the antipruritic effect of locally administered ethyl acetate extract from Fructus cnidii (EAEFC) to 2,4-dinitrofluorobenzene- (DNFB-) induced AD in a mouse model. The scratching behavior, skin thickness, dermatitis score, weight, blood immunoglobulin E (IgE) level, and itch-related cytokine levels were subsequently monitored and evaluated. Results showed that EAEFC treatment attenuated the DNFB-induced AD-like symptoms by alleviating the skin lesions and decreasing the dermatitis score. Hematoxylin and eosin (H&E) and toluidine blue (TB) staining analyses demonstrated that EAEFC mitigated the DNFB-induced increase in skin thickness and prevented the infiltration of mast cells. Behavioral tests showed that EAEFC decreased the DNFB-induced acute and chronic scratching behaviors. Furthermore, EAEFC reduced the levels of itch-related cytokines, such as thymic stromal lymphopoietin (TSLP), interleukin- (IL-) 17, IL-33, and IL-31, and the DNFB-induced boost in serum IgE. Collectively, these results suggest that EAEFC is a potential therapeutic candidate for the treatment of chronic itch in AD.

16.
Nanoscale Horiz ; 5(3): 530-540, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32118209

RESUMO

Lithium-sulfur batteries (LSBs) have gained considerable attention for their desirable energy densities, high theoretical capacities, low cost and environmentally friendly properties. However, the shuttle effect of polysulfides seriously hinders their future practical applications. Herein, a dual-function cathode structure, consisting of 3D porous FeP/rGO microspheres supported on both aluminum foil and a commercial separator, exhibits excellent performance by providing strong adsorption with respect to Li2Sx (x = 1, 2, 4, 6 and 8) and S8. In this rational design, the iron phosphide (FeP) nanoparticles act as a catalyst to accelerate polysulfide conversion and as the designated sites for adsorption. The 3D rGO porous conductive network can provide enough space for sulfur loading and to physically adsorb the polysulfides. More importantly, density functional theory (DFT) calculations also verified the strong interactions (with adsorption energy values of -4.21 to -1.97 eV) between the FeP(111) surface and the sulfur species. The electrochemical results show that the cell using the dual-function cathode structure delivers a capacity of 925.7 mA h g-1, with capacity degradation of 0.05% per cycle after 500 cycles, at a current density of 0.5C. It is also worth mentioning that the cell with sulfur loading of ∼2.2 mg cm-2 maintained a high capacity of 483 mA h g-1 at 0.5C after 500 cycles. In summary, the above results demonstrate the promising application of the dual-function cathode structure for high-performance LSBs.

17.
Opt Express ; 27(22): 32392-32397, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684453

RESUMO

Phase-shifting holography has been widely applied in the field of non-destructive testing and interference imaging. Compared to the previous single-shot phase-shifting holography, here tri-focal Fibonacci-Billet split lens was introduced into Mach-Zehnder interferometer, in which the upper half of the Fibonacci-Billet split lens can realize three phase-locking copies of the planar reference wave and the lower half is used to generate three identical copies of object. The interference pattern is recorded by a detector in one single exposure. The test object can be reconstructed by three-step phase-shifting interferometry. The corresponding experiment is carried out to verify the effectiveness of this method. With advantages of real-time reconstruction and amplitude-only diffraction lens, it is very useful for fast imaging and optical element detection.

18.
Nanoscale Res Lett ; 14(1): 326, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31624928

RESUMO

The reasonable design of nanostructure is the key to solving the inherent defects and realizing a high performance of Li2FeSiO4 cathode materials. In this work, a novel heterostructure CNT@Li2FeSiO4@C has been designed and synthesized and used as a cathode material for lithium-ion battery. It is revealed that the product has a uniform core-shell structure, and the thickness of the Li2FeSiO4 layer and the outer carbon layer is about 19 nm and 2 nm, respectively. The rational design effectively accelerates the diffusion of lithium ions, improves the electric conductivity, and relieves the volume change during the charging/discharging process. With the advantages of its specific structure, CNT@Li2FeSiO4@C has successfully overcome the inherent shortcomings of Li2FeSiO4 and shown good reversible capacity and cycle properties.

19.
Nanoscale ; 11(22): 11025-11032, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31140522

RESUMO

As a promising energy storage device, sodium ion batteries (SIBs) have attracted more and more attention. Nevertheless, the radius of a sodium ion is much larger than that of a lithium ion, and it is still a significant challenge to solve the problem of volume expansion. In order to solve the problem of volume expansion, a rational nanostructure consisting of CNTs as a carbon matrix, and were sequentially coated with mesoporous SnO2 and N-doped porous carbon tube (NCT). Mesoporous SnO2 can alleviate the volume expansion caused by charge and discharge, and the N-doped porous carbon layer can further inhibit the volume expansion of SnO2. When used as an anode material in sodium ion batteries, the CNT@SnO2@NCT heterostructure achieves efficient capabilities (350 and 150 mA h g-1 at current densities of 0.1 and 2 A g-1, respectively).

20.
Nanoscale Res Lett ; 14(1): 79, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30838476

RESUMO

Up to date, the way in which metal nanoparticles are cleared in vivo has yet to be elucidated well. Herein, we report a novel intestinal goblet cell-mediated in vivo clearance pathway to remove metal nanoparticles. Typical metal nanoparticles such as triangular silver nanoplates, magnetic nanoparticles, gold nanorods, and gold nanoclusters were selected as representative examples. These metal nanoparticles were prepared, characterized, and injected via tail vein into a mice model with common bile duct (CBD) ligation. The feces and urines were collected for 7 days to be followed by the sacrifice of the mice and collection of the intestinal and gastric tissues for further analysis. The results showed that all four selected metal nanoparticles were located inside the goblet cells (GCs) of the whole intestinal tissue and were excreted into the gut lumen through the secretion of intestinal GC. Moreover, triangular silver nanoplates and gold nanorods were located inside the gastric parietal cells (PCs). Importantly, nanoparticles did not cause obvious pathological changes in intestinal tissues. In this study, we confirmed that the blood corpuscles are involved in the GCs secretion pathway. Furthermore, we found that the secretion of nanoparticles from intestinal GCs and PCs is accelerated by diarrhea induced via Chinese herbs. In conclusion, metal nanoparticles such as triangular silver nanoplates, magnetic nanoparticles, gold nanorods, and gold nanoclusters can be cleaned away by intestinal GCs and PCs. This novel pathway of in vivo clearance of metal nanoparticles has a great potential for future applications such as new drug design and development, nanoparticle-based labeling and in vivo tracking, and biosafety evaluation of in vivo nanoparticles.

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