Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
ACS Appl Mater Interfaces ; 14(28): 31803-31813, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35792003

RESUMO

Metal phosphides are promising candidates for sodium-ion battery (SIB) anode owing to their large capacities with suitable redox potential, while the reversibility and rate performances are limited due to some electrochemically inactive transition-metal components and sluggish reaction kinetics. Here, we report a fully active bimetallic phosphide Zn0.5Ge0.5P anode and its composite (Zn0.5Ge0.5P-C) with excellent performance attributed to the Zn, Ge, and P components exerting their respective Na-storage merit in a cation-disordered structure. During Na insertion, Zn0.5Ge0.5P undergoes an alloying-type reaction, along with the generation of NaP, Na3P, NaGe, and NaZn13 phases, and the uniform distribution of these phases ensures the electrochemical reversibility during desodiation. Based on this reaction mechanism, excellent electrochemical properties such as a high reversible capacity of 595 mAh g-1 and an ultrafast charge-discharge capability of 377.8 mAh g-1 at 50C for 500 stable cycles were achieved within the Zn0.5Ge0.5P-C composite in a diglyme-based electrolyte. This work reveals the Na-storage reaction mechanism within Zn0.5Ge0.5P and offers a new perspective on designing high-performance anodes.

2.
J Colloid Interface Sci ; 607(Pt 2): 1253-1261, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34583032

RESUMO

Advanced integrated electrode materials with designedcore-shell nanostructureplay a crucial role for the application in alternative energy storage system. Herein, hierarchical MoO3@NixCo2x(OH)6x core-shell arrays were equably grown on face of carbon cloth after a series of hydrothermal growth and electrochemical deposition processes. This core-shell arrays structure can not only provide large electroactive surface areas and high speed ion transport paths, but also keep the material structure stable during the process of redox reactions. Thus MoO3@NixCo2x(OH)6x displays excellent electrochemical performance (4.7 F cm-2 at 10 mA cm-2). Moreover, the asymmetric supercapacitor is assembled with MoO3@NixCo2x(OH)6x and carbon nanotubes, which delivers a maximal energy density of 0.50 mWh cm-2 at 4.25 mW cm-2, high specific capacitance and superior cycling stability (94.5% capacitance retention after 5000 cycles). We believe that MoO3@NixCo2x(OH)6x arrays could be a great prospective candidate energy storage materials.

3.
J Colloid Interface Sci ; 601: 669-677, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34091314

RESUMO

A facile "carbon quantum dots glue" strategy for the fabrication of honeycomb-like carbon quantum dots/nickel sulphide network arrays on Ni foam surface is successfully demonstrated. This design realizes the immobilization of nanosheet arrays and maintains a strong adhesion to the collector, forming a three-dimensional (3D) honeycomb-like architecture. Thanks to the unique structural advantages, the resulting bind-free electrode with high active mass loading of 6.16 mg cm-2 still exhibits a superior specific capacitance of 1130F g-1 at 2 A g-1, and maintains 80% of the initial capacitance even at 10 A g-1 after 3000 cycles. Furthermore, the assembled asymmetrical supercapacitor delivers an energy density of 18.8 Wh kg-1 at a power density of 134 W kg-1, and outstanding cycling stability (100% of initial capacitance retention after 5000 cycles at 5 mA cm-2). These impressive results indicate a new perspective to design various binder-free electrodes for electrochemical energy storage devices.

4.
Nanotechnology ; 32(29)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33836514

RESUMO

An integrated electrode of core-shell coaxially structured NiCo2S4@TiO2nanorod arrays/carbon cloth (NiCo2S4@TiO2@CC) have been fabricated, via a two-step hydrothermal method. Comprehensive structural and compositional analyzes are performed to understand the effects of the NiCo2S4shell on the TiO2core. Such core-shell arrays structure can significantly provide abundant electroactive sites for redox reactions, convenient ion transport paths, and favorable structure stability. The NiCo2S4@TiO2@CC electrode represents a splendid specific capacitance (650 F g-1at 1 A g-1) and enhanced cycling stability (capacitance retention of 97% over 10 000 cycles at 5 A g-1). Additionally, the assembled NiCo2S4@TiO2@CC//CNT@CC solid-state asymmetric supercapacitors exhibit a maximal energy density of 0.6 mWh cm-3at 32.4 W cm-3, and topping cycling stability (85% capacitance retention after 5000 cycles at 5 mA cm-2). The results demonstrate that the well-designed NiCo2S4@TiO2@CC presented in this work are applicable for the development of electrode materials in energy storage devices.

5.
J Colloid Interface Sci ; 587: 302-310, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33360903

RESUMO

A hierarchical NiGa2O4@MnO2 core-shell nanowall arrays have been grown on carbon cloth by stepwise design and fabrication. Ultrathin MnO2 nanoflakes are revealed to grow uniformly on the porous NiGa2O4 nanowalls with many interparticle mesopores, resulting in the formation of 3D core-shell nanowall arrays with hierarchical architecture. The as-synthesized product as a binder-free electrode possesses a high specific capacitance of 1700 F g-1 at 1 A g-1 and 90% capacitance retention after 10,000 cycles at 10 A g-1. Furthermore, an asymmetrical solid-state supercapacitor assembled by the NiGa2O4@MnO2 and N-CMK-3 exhibits an energy density of 0.59 Wh cm-3 at a power density of 48 W cm-3, and excellent cycling stability (80% of initial capacitance retention after 5000 cycles at 6 mA cm-2). The remarkable electrochemical performances can be attributed to its novel nanostructure with high surface area, convenient ion transport paths and favorable structure stability. These results display an effective method for fabrication of different core-shell nanostructure on conductive substrates, which brings new design opportunities of device configuration for next energy storage devices.

6.
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.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...