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1.
ACS Nano ; 18(18): 11804-11812, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38650374

RESUMO

Nuclear power plays a pivotal role in the global energy supply. The adsorption-based extraction of uranium from seawater is crucial for the rapid advancement of nuclear power. The phosphorus nitride imide (PN) nanotubes were synthesized in this study using a solvothermal method, resulting in chemically stable cross-linked tubular hollow structures that draw inspiration from the intricate snowflake fractal pattern. Detailed characterization showed that these nanotubes possess a uniformly distributed five-coordinated nanopocket, which exhibited great selectivity and efficiency in binding uranium. PN nanotubes captured 97.34% uranium from the low U-spiked natural seawater (∼355 µg L-1) and showed a high adsorption capacity (435.58 mg g-1), along with a distribution coefficient, KdU > 8.71 × 107 mL g-1. In addition, PN nanotubes showed a high adsorption capacity of 7.01 mg g-1 in natural seawater. The facile and scalable production of PN nanotubes presented in this study holds implications for advancing their large-scale implementation in the selective extraction of uranium from seawater.

2.
Biomater Sci ; 12(9): 2446-2447, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38602355

RESUMO

Correction for 'Clodronate-nintedanib-loaded exosome-liposome hybridization enhances the liver fibrosis therapy by inhibiting Kupffer cell activity' by Keqin Ji et al., Biomater. Sci., 2022, 10, 702-713, https://doi.org/10.1039/D1BM01663F.

3.
Small ; 20(22): e2306536, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38168889

RESUMO

Effective strategies toward building exquisite nanostructures with enhanced structural integrity and improved reaction kinetics will carry forward the practical application of alloy-based materials as anodes in batteries. Herein, a free-standing 3D carbon nanofiber (CNF) skeleton incorporated with heterostructured binary metal selenides (ZnSe/SnSe) nanoboxes is developed for Na-ion storage anodes, which can facilitate Na+ ion migration, improve structure integrity, and enhance the electrochemical reaction kinetics. During the carbonization and selenization process, selenium/nitrogen (Se/N) is co-doped into the 3D CNF skeleton, which can improve the conductivity and wettability of the CNF matrices. More importantly, the ZnSe/SnSe heterostructures and the Se/N co-doping CNFs can have a synergistic interfacial coupling effect and built-in electric field in the heterogeneous interfaces of ZnSe/SnSe hetero-boundaries as well as the interfaces between the CNF matrix and the selenide heterostructures, which can enable fast ion/electron transport and accelerate surface/internal reaction kinetics for Na-ion storage. The ZnSe/SnSe@Se,N-CNFs exhibit superior Na-ion storage performance than the comparative ZnSe/SnSe, ZnSe and SnSe powders, which deliver an excellent rate performance (882.0, 773.6, 695.7, 634.2, and 559.0 mAh g-1 at current rates of 0.1, 0.2, 0.5, 1, and 2 A g-1) and long-life cycling stability of 587.5 mAh g-1 for 3500 cycles at 2 A g-1.

4.
ACS Nano ; 17(11): 10113-10128, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37229569

RESUMO

The extracellular matrix (ECM) is a major driver of fibrotic diseases and forms a dense fibrous barrier that impedes nanodrug delivery. Because hyperthermia causes destruction of ECM components, we developed a nanoparticle preparation to induce fibrosis-specific biological hyperthermia (designated as GPQ-EL-DNP) to improve pro-apoptotic therapy against fibrotic diseases based on remodeling of the ECM microenvironment. GPQ-EL-DNP is a matrix metalloproteinase (MMP)-9-responsive peptide, (GPQ)-modified hybrid nanoparticle containing fibroblast-derived exosomes and liposomes (GPQ-EL) and is loaded with a mitochondrial uncoupling agent, 2,4-dinitrophenol (DNP). GPQ-EL-DNP can specifically accumulate and release DNP in the fibrotic focus, inducing collagen denaturation through biological hyperthermia. The preparation was able to remodel the ECM microenvironment, decrease stiffness, and suppress fibroblast activation, which further enhanced GPQ-EL-DNP delivery to fibroblasts and sensitized fibroblasts to simvastatin-induced apoptosis. Therefore, simvastatin-loaded GPQ-EL-DNP achieved an improved therapeutic effect on multiple types of murine fibrosis. Importantly, GPQ-EL-DNP did not induce systemic toxicity to the host. Therefore, the nanoparticle GPQ-EL-DNP for fibrosis-specific hyperthermia can be used as a potential strategy to enhance pro-apoptotic therapy in fibrotic diseases.


Assuntos
Matriz Extracelular , Hipertermia Induzida , Camundongos , Animais , Fibrose , Colágeno/farmacologia , Fibroblastos
5.
Nanotechnology ; 34(22)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36857776

RESUMO

Oxygen evolution reaction (OER) is a necessary procedure in various devices including water splitting and rechargeable metal-air batteries but required a higher potential to improve oxygen evolution efficiency due to its slow reaction kinetics. In order to solve this problem, a heterostructured electrocatalyst (Co3O4@FeOx/CC) is synthesized by deposition of iron oxides (FeOx) on carbon cloth (CC) via plasma-enhanced atomic layer deposition, then growth of the cobalt oxide (Co3O4) nanosheet arrays. The deposition cycle of FeOxon the CC strongly influences thein situgrowth and distribution of Co3O4nanosheets and electronic conductivity of the electrocatalyst. Owing to the high accessible and electroactive areas and improved electrical conductivity, the free-standing electrode of Co3O4@FeOx/CC with 100 deposition cycles of FeOxexhibits excellent electrocatalytic performance for OER with a low overpotential of 314.0 mV at 10 mA cm-2and a small Tafel slope of 29.2 mV dec-1in alkaline solution, which is much better than that of Co3O4/CC (448 mV), and even commercial RuO2(380 mV). This design and optimization strategy shows a promising way to synthesize ideally designed catalytic architectures for application in energy storage and conversion.

6.
Nanoscale ; 15(5): 2435, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36656034

RESUMO

Correction for 'Long cyclic stability of acidic aqueous zinc-ion batteries achieved by atomic layer deposition: the effect of the induced orientation growth of the Zn anode' by Zhisen Zeng et al., Nanoscale, 2021, 13, 12223-12232, https://doi.org/10.1039/d1nr02620h.

7.
Nanomicro Lett ; 14(1): 154, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35916945

RESUMO

Large volumetric expansion of cathode hosts and sluggish transport kinetics in the cathode-electrolyte interface, as well as dendrite growth and hydrogen evolution at Zn anode side are considered as the system problems that cause the electrochemical failure of aqueous Zn-vanadium oxide battery. In this work, a multifunctional anti-proton electrolyte was proposed to synchronously solve all those issues. Theoretical and experimental studies confirm that PEG 400 additive can regulate the Zn2+ solvation structure and inhibit the ionization of free water molecules of the electrolyte. Then, smaller lattice expansion of vanadium oxide hosts and less associated by-product formation can be realized by using such electrolyte. Besides, such electrolyte is also beneficial to guide the uniform Zn deposition and suppress the side reaction of hydrogen evolution. Owing to the integrated synergetic modification, a high-rate and ultrastable aqueous Zn-V2O3/C battery can be constructed, which can remain a specific capacity of 222.8 mAh g-1 after 6000 cycles at 5 A g-1, and 121.8 mAh g-1 even after 18,000 cycles at 20 A g-1, respectively. Such "all-in-one" solution based on the electrolyte design provides a new strategy for developing high-performance aqueous Zn-ion battery.

8.
Artigo em Inglês | MEDLINE | ID: mdl-35836309

RESUMO

For most alloying- and conversion-type anode materials, a huge volume expansion and structure degradation of the electrodes always hinder their applications. In this work, a novel core-shell-shell Sb2S3/Sb@TiO2@C nanorod composite has been designed layer by layer, which includes an inner Sb2S3/Sb heterostructure core protected by an oxygen-deficient TiO2 shell and a conductive carbon shell. It is interesting to observe that, during the carbothermic reduction process, the previous Sb2S3 nanorod cores are partially reduced into a metallic Sb phase and the reduced TiO2 also creates many oxygen vacancies, which can greatly enhance the conductivity of the semiconductor Sb2S3. Thanks to the double effects of the TiO2 middle shell and carbon outer shell, the unique double-shelled structure design creates an enhanced dual protection, which can better accommodate the volume-expansive deformation and preserve the structural integrity of the active Sb2S3/Sb core. Especially, the TiO2 middle layer is self-assembled by numerous nanoparticles acting as a nanopillar backbone, which supports between the nanorod core and outer carbon shell to better buffer the volume changes. As a result, the core-shell-shell Sb2S3/Sb@TiO2@C anode shows lithium and sodium storage performances superior to those of the pristine Sb2S3 and core-shell Sb2S3@TiO2 electrodes. For lithium-ion batteries, the Sb2S3/Sb@TiO2@C nanorod composite achieves an initial discharge/recharge capacity of 1244.9/1005.1 mAh g-1 with an initial Coulombic efficiency of about 80.7%, an enhanced rate capability with a capacity of 593.2 mA h g-1 at 5.0 A g-1, and prolonged cycling life for 500 cycles with a reversible capacity of 495.8 mAh g-1 at 0.5 A g-1. For sodium-ion batteries, the nanorodalso exhibits an improved performance with an initial discharge/recharge capacity of 781.4/574.0 mAh g-1 (initial Coulombic efficiency of about 73.46%) and cycling for 400 cycles with a reversible capacity of 422.6 mAh g-1 at 0.8 A g-1. This research sheds light upon double-shell structure designs with an effective middle shell to enhance the energy storage performance of electrode materials.

9.
Small Methods ; 6(7): e2200207, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35656764

RESUMO

It remains a challenge to develop cost-effective, high-performance oxygen electrocatalysts for rechargeable metal-air batteries. Herein, zinc-mediated zeolitic imidazolate frameworks are exploited as the template and nitrogen and carbon sources, onto which is deposited a Fe3 O4 layer by plasma-enhanced atomic layer deposition. Controlled pyrolysis at 1000 °C leads to the formation of high density of Fe3 O4- x few-atom clusters with abundant oxygen vacancies deposited on an N-doped graphitic carbon framework. The resulting nanocomposite (Fe3 O4- x /NC-1000) exhibits a markedly enhanced electrocatalytic performance toward oxygen reduction reaction in alkaline media, with a remarkable half-wave potential of +0.930 V versus reversible hydrogen electrode, long-term stability, and strong tolerance against methanol poisoning, in comparison to samples prepared at other temperatures and even commercial Pt/C. Notably, with Fe3 O4- x /NC-1000 as the cathode catalyst, a zinc-air battery delivers a high power density of 158 mW cm-2 and excellent durability at 5 mA cm-2 with stable 2000 charge-discharge cycles over 600 h. This is ascribed to the ready accessibility of the Fe3 O4- x catalytic active sites, and enhanced electrical conductivity, oxygen adsorption, and electron-transfer kinetics by surface oxygen vacancies. Further contributions may arise from the highly conductive and stable N-doped graphitic carbon frameworks.

10.
J Hazard Mater ; 434: 128894, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35447534

RESUMO

In order to deal with the environmental resource problems caused by nuclear pollution and uranium mine wastewater, it is particularly important to develop uranium removal adsorbent materials with low cost, high efficiency and controllable rapid preparation. In this work, the hollow grape-like manganese phosphate clusters (h-MnPO4) were synthesized in 4 h by in-situ etching without template at room temperature, which can quickly and effectively remove uranium ions from wastewater. Due to the reasonable hollow structure, more effective adsorption sites are exposed. The obtained sample h-MnPO4-200 reaches adsorption equilibrium in 1 h and can remove 97.20% uranyl ions (initial concentration is 100 mg L-1). Under the condition of 25 â„ƒ and pH= 4, the maximum adsorption capacity of h-MnPO4-200 for uranium was 751.88 mg g-1. The FT-IR, XPS and XRD analysis showed that -OH and PO43- groups played a key role in the adsorption process. Thanks to the synergistic adsorption mechanism of surface complexation and dissolution-precipitation, h-MnPO4-200 maintained a high removal rate in the presence of competitive anions and cations. In a word, h-MnPO4-200 can be rapidly synthesized through a facile and low-cost method and has a great application prospect in the practical emergency treatment of uranium-containing wastewater.


Assuntos
Urânio , Vitis , Adsorção , Cátions/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Urânio/química , Águas Residuárias/análise
11.
Nanoscale ; 14(6): 2490-2501, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35103274

RESUMO

Although the design and synthesis of efficient electrocatalysts for the hydrogen evolution reaction (HER) are highly desirable, severe challenges still need to be addressed. Herein, ultrathin MoS2 nanosheets were vertically grown on CoSe2 hollow nanotube arrays via a simple three-step hydrothermal reaction by using carbon cloth (CC) as a substrate and were subsequently used as a highly efficient HER electrocatalyst (MoS2@CoSe2-CC hybrid). The MoS2 nanosheets uniformly self-assembled on conductive CoSe2 nanotube arrays exhibited a hierarchical and well-ordered structure. Such a unique structure may not only comprise more exposed active sites, but also enable fast electrolyte penetration and facilitate H+/electron transportation to accelerate the reduction and evolution of H2 during the electrocatalytic process. As an HER electrocatalyst with a novel three-dimensional hierarchical structure, the MoS2@CoSe2-CC hybrid exhibited an outstanding catalytic HER performance with a small Tafel slope of 67 mV dec-1 in alkaline media, while only requiring a low HER overpotential of 101 mV at 10 mA cm-2. Notably, the MoS2@CoSe2-CC hybrid also demonstrated exceptional electrochemical durability and structural stability even after 1000 cycles or 48 h of continuous electrolysis. Overall, this work presents a new approach for the design and synthesis of robust, highly active, and cost-effective electrocatalysts for hydrogen generation.

12.
Biomater Sci ; 10(3): 702-713, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34927632

RESUMO

Liver fibrosis therapy remains limited due to the inefficiency of drug delivery and inflammation induced by Kupffer cells. In this study, an exosome-liposome hybrid drug delivery system (LIEV) was developed to increase the efficacy of clodronate (CLD)-inhibition of Kupffer cells and to effectively deliver nintedanib (NIN) to liver fibroblasts to ensure enhanced anti-fibrosis therapy. CLD and NIN co-loaded LIEV (CLD/NIN@LIEV) exerted non-specific inhibition of phagocytosis by Kupffer cells, reduced inflammatory cytokines, and showed homologous homing properties mediated by fibroblast-derived exosomes, thereby achieving superior antifibrotic effects in a CCl4-induced fibrosis mouse model by inhibiting the proliferation of fibroblasts. Furthermore, the inhibited Kupffer cells regenerated within 10 days after dosage withdrawal. Unlike carrier-free NIN treatment, CLD/NIN@LIEV induced a marked decrease in liver enzymes, indicating improved safety and anti-fibrosis efficacy. These results indicate its great potential for treatment with the combined anti-fibrosis agent and Kupffer cell inhibition strategies to enhance the liver fibrosis therapy.


Assuntos
Exossomos , Células de Kupffer , Animais , Ácido Clodrônico/farmacologia , Fibrose , Indóis , Células de Kupffer/patologia , Lipossomos , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Camundongos
13.
Front Cell Infect Microbiol ; 12: 919701, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36683686

RESUMO

Faecalibacterium prausnitzii is a beneficial human gut microbe and a candidate for next-generation probiotics. With probiotics now being used in clinical treatments, concerns about their safety and side effects need to be considered. Therefore, it is essential to obtain a comprehensive understanding of the genetic diversity, functional characteristics, and potential risks of different F. prausnitzii strains. In this study, we collected the genetic information of 84 F . prausnitzii strains to conduct a pan-genome analysis with multiple perspectives. Based on single-copy genes and the sequences of 16S rRNA and the compositions of the pan-genome, different phylogenetic analyses of F. prausnitzii strains were performed, which showed the genetic diversity among them. Among the proteins of the pan-genome, we found that the accessory clusters made a greater contribution to the primary genetic functions of F. prausnitzii strains than the core and specific clusters. The functional annotations of F. prausnitzii showed that only a very small number of proteins were related to human diseases and there were no secondary metabolic gene clusters encoding harmful products. At the same time, complete fatty acid metabolism was detected in F. prausnitzii. In addition, we detected harmful elements, including antibiotic resistance genes, virulence factors, and pathogenic genes, and proposed the probiotic potential risk index (PPRI) and probiotic potential risk score (PPRS) to classify these 84 strains into low-, medium-, and high-risk groups. Finally, 15 strains were identified as low-risk strains and prioritized for clinical application. Undoubtedly, our results provide a comprehensive understanding and insight into F. prausnitzii, and PPRI and PPRS can be applied to evaluate the potential risks of probiotics in general and to guide the application of probiotics in clinical application.


Assuntos
Faecalibacterium prausnitzii , Probióticos , Humanos , Faecalibacterium prausnitzii/genética , Faecalibacterium prausnitzii/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Variação Genética
14.
Nanoscale ; 13(28): 12223-12232, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34240091

RESUMO

Aqueous Zn-ion batteries with economical ZnSO4 solution as the electrolyte suffer from a tremendous tendency of dendrite formation under mildly acidic conditions; moreover, utilization of Zn(CF3SO3)2 delivers superior performance, but is expensive. Herein, we optimize the ZnSO4 electrolyte by inducing 50 µL of 10 M sulfuric acid in 10 mL electrolyte, which can achieve long cycle life (1000 h at 0.1 mA cm-2, 300 h at 1 mA cm-2 and 250 h at 10 mA cm-2) when the Zn foil is protected by three metallic oxides deposited by atomic layer deposition (ALD). The nucleation behaviour of the (002) facet has proved to play a critical role in the reversible lifespan. The Al2O3 layer would restrict the stripping procedure, leading to the highest overpotential, while the TiO2 layer and Fe2O3 layer tended to strip all orientations but the (002) facet. Al2O3@Zn demonstrated a preference for a compact hillock-like (101) orientation texture in the deposition procedure, while TiO2@Zn and Fe2O3@Zn were favourable to obtain a smooth terrace texture. Additionally, symmetric cells with Fe2O3@Zn expressed the lowest overpotential (31.64 mV) and minimal voltage hysteresis (23.6 mV) at 1 mA cm-2. A Zn-MnO2 battery with Fe2O3@Zn also displayed superior capacity, which could reach 280 mA h g-1 at a current density of 1 A g-1. The diffusion coefficient of Zn2+ discloses that among the three ALD layers, full cells with Fe2O3@Zn are the most favourable for diffusion of Zn2+ in acidic electrolyte.

15.
Biomaterials ; 271: 120761, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33774524

RESUMO

Pulmonary fibrosis is a rapidly progressive and fatal fibrotic lung disease with high mortality and morbidity. However, pulmonary fibrosis therapy in the clinic has been limited by poor selectivity and inefficiency of drug delivery to fibroblasts. Herein, a clodronate (CLD)-loaded liposome and fibroblast-derived exosome (EL-CLD) hybrid drug delivery system with non-specific phagocytosis inhibition and fibroblast homing properties, was designed for the treatment of pulmonary fibrosis. EL-CLD effectively depleted Kupffer cells via apoptosis by passive targeting after intravenous injection, and thus significantly reduced accumulation in the liver. Notably, the EL-CLD hybrid system preferentially accumulated in the fibrotic lung, and significantly increased penetration inside pulmonary fibrotic tissue by targeted delivery due to the specific affinity for fibroblasts of the homologous exosome. Nintedanib (NIN), an anti-fibrotic agent used to treat pulmonary fibrosis, was loaded in the EL-CLD system, and achieved a remarkable improvement in curative effects. The enhanced therapeutic efficacy of NIN was a result of enhanced pulmonary fibrotic tissue accumulation and delivery, combined with a diminished macrophage-induced inflammatory response. Hence, the EL-CLD hybrid system acts as an efficient carrier for pulmonary anti-fibrotic drug delivery and should be developed as an efficient fibroblast specific therapy.


Assuntos
Ácido Clodrônico , Fibrose Pulmonar , Fibroblastos , Humanos , Lipossomos , Pulmão , Macrófagos , Fibrose Pulmonar/tratamento farmacológico
16.
J Pharm Pharmacol ; 73(9): 1212-1217, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-33772549

RESUMO

OBJECTIVES: Ovarian cancer is a lethal gynecological malignancy. Long non-coding RNA antisense non-coding RNA in the INK4 locus (lncRNA ANRIL) was reported to have a critical role in cancer advancement. The ANRIL-mediated oncogenic underlying molecular mechanisms are not fully understood in ovarian cancer. We aimed to study ANRIL silencing effects on the proliferation and apoptosis of OVCAR-3 cells. METHODS: The ANRIL was Knockdown by transfection of OVCAR-3 cells with si-RNA against ANRIL. MTT assay and cell death ELISA kit were used to evaluate cellular proliferation and apoptosis. The expression levels of ANRIL, pro-and anti-apoptotic genes were assessed using q-RT-PCR. Western blotting was used to assess Wnt/ß-catenin signalling pathway. KEY FINDINGS: ANRIL down-regulating in OVCAR-3 cell lines resulted in significant inhibition of cellular proliferation, apoptosis induction, as well as suppression of cellular invasion. Besides, knockdown of ANRIL led to pro-apoptotic genes up-regulation, Bad and Bax and anti-apoptotic genes down-regulation, Bid and Bcl-2. More importantly, we observed that ANRIL inhibition suppressed the vital components expression of the Wnt/ß-catenin cascade. CONCLUSION: Our findings showed that down-regulation of lncRNA ANRIL resulted in the effective suppression of OVCAR-3 cell proliferation and invasion and induction of apoptosis by preventing Wnt/ß-catenin signal transduction.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/genética , Ovário , RNA Longo não Codificante/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Feminino , Humanos , MicroRNAs , Invasividade Neoplásica , Neoplasias Ovarianas/metabolismo , Ovário/metabolismo , Ovário/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais
17.
J Pers Med ; 11(2)2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33672813

RESUMO

The use of nanomedicine for antitumor therapy has been extensively investigated for a long time. Enhanced permeability and retention (EPR) effect-mediated drug delivery is currently regarded as an effective way to bring drugs to tumors, especially macromolecular drugs and drug-loaded pharmaceutical nanocarriers. However, a disordered vessel network, and occluded or embolized tumor blood vessels seriously limit the EPR effect. To augment the EPR effect and improve curative effects, in this review, we focused on the perspective of tumor blood vessels, and analyzed the relationship among abnormal angiogenesis, abnormal vascular structure, irregular blood flow, extensive permeability of tumor vessels, and the EPR effect. In this commentary, nanoparticles including liposomes, micelles, and polymers extravasate through the tumor vasculature, which are based on modulating tumor vessels, to increase the EPR effect, thereby increasing their therapeutic effect.

18.
Nanoscale ; 13(6): 3782-3789, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33564809

RESUMO

SnTe exhibits a layered crystal structure, which enables fast Li-ion diffusion and easy storage, and is considered to be a promising candidate for an advanced anode material. However, its applications are hindered by the large volume variation caused by intercalation/deintercalation during the electrochemical reaction processes. Herein, topological insulator SnTe and carbon nanotubes (CNTs) supported on a graphite (G) carbon framework (SnTe-CNT-G) were prepared as a new, active and robust anode material for high-rate lithium-ion batteries by a scalable ball-milling method. Remarkably, the SnTe-CNT-G composite used as a lithium-ion battery anode offered an excellent reversible capacity of 840 mA h g-1 at 200 mA g-1 after 100 cycles and high initial coulombic efficiencies of 76.0%, and achieved a long-term cycling stability of 669 mA h g-1 at 2 A g-1 after 1400 cycles. The superior electrochemical performance of SnTe-CNT-G is attributed to the stable design of its electrode structure and interesting topological transition of SnTe, combined with multistep conversion and alloying processes. Furthermore, in situ X-ray diffraction and ex situ X-ray photoelectron spectroscopy were employed to study the reaction mechanism. The results presented here provide new insights to design and reveal the reaction mechanisms of transition metal telluride materials in various energy-storage materials.

19.
Nanoscale ; 13(5): 3227-3236, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33528482

RESUMO

The rational design and construction of the efficient and robust non-noble metal bifunctional oxygen electrocatalysts is of critical significance due to the attention given to reversible metal-air batteries. In this paper, we report novel two-dimensional "senbei"-like Co9S8/CeO2/Co-NC nitrogen-doped carbon nanosheets (Co9S8/CeO2/Co-NC) derived from a unique 2D Co/Ce bimetallic ZIF. The phase transition from 3D spherical Co-ZIF to 2D Co/Ce-ZIF was achieved through the introduction of Ce ions. Profiting from the successful construction of the unique Co9S8/CeO2 heterostructure and the synergetic effect of two components, the as-prepared Co9S8/CeO2/Co-NC exhibited excellent electro-performance in both the oxygen evolution reaction (Ej=10 = 1.60 V) and oxygen reduction reaction (E1/2 = 0.875 V). Furthermore, when used as a bifunctional air electrode for Zn-air batteries, Co9S8/CeO2/Co-NC reached a high peak power density of ≈164.24 mW cm-2 at a high current density of ≈351 mA cm-2 and displayed an outstanding cycling stability of more than 668 h at 5 mA cm-2. This research provides new guidelines for preparing hybrid materials from cobalt-based sulfide species and CeO2 for electrocatalysis and energy storage or other fields.

20.
Nanoscale ; 12(42): 21770-21779, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33095215

RESUMO

To improve the high reversibility of lithium-air batteries, an air electrode needs to have excellent electrochemical performance and spatial structure. Ni3S2 nanoparticles are loaded onto an N,S-doped pearl chain tube (N,S-PCT) by a method called quasi-chemical vapor deposition (Q-CVD). Additionally, N and S are doped during the synthesis process, thereby forming an ideal pipe rack-like structure. The large amount of space in the tube rack can provide sufficient storage to act as a buffer for the discharge products, and the interconnected tubes can effectively promote the dispersion of O2 and electrolyte. The addition of Ni3S2 nanoparticles effectively reduces the charge transfer resistance, thereby increasing the electron mobility of the cathode. Ni3S2@N,S-PCT cathodes effectively improve the cycling and high-rate performance of lithium-air batteries, demonstrating an ultrahigh discharge capacity of 16 733.7 mA h g-1 at a current density of 400 mA g-1 and an ultrahigh discharge capacity of 5088.1 mA h g-1 at a current density of 1000 mA g-1. When the cut-off capacity is 1000 mA h g-1, the battery with the Ni3S2@N,S-PCT-800 electrode can achieve cycling stability for 148 cycles. This research provides a new solution for the design of lithium-air batteries with high electrocatalytic performance.

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